JEF And European Security

The Joint Expeditionary Force (JEF) is a UK-led, 10-member defence framework focused on northern Europe. In September 2014, at the NATO Wales Summit, the JEF signed its founding Letter of Intent to develop a rapidly deployable force to operate across the full spectrum of operations.

During its first decade, the JEF has made an important contribution to European security. Owing to its design and development, the JEF exhibits several comparative advantages over other European defence and security frameworks: it has political and military leadership, it is flexible and better able to respond to crises, and it has regional expertise and a combined military heft which is increasingly valuable to NATO.

Following the 2014 Russian annexation of Crimea and incursion into the Donbas, the JEF participants responded by collectively increasing their defence expenditure so that all members now meet the NATO 2% of GDP target (up from just one member – the UK), and established a command-and-control structure, annual military and ministerial exercises, and interoperability programmes.

The JEF’s established programme of work allowed it to be quick to respond to Russia’s 2022 invasion of Ukraine. It immediately developed a political dimension, through national Leaders’ Summits, which provided a unifying framework to advocate for the defence of Ukraine, pushed for a stronger unified position against Russia, and pressured other NATO members to step up. As such, it has collectively committed more diplomatic, military and humanitarian assistance to Ukraine than the rest of non-US NATO members combined.

Following these successes, in 2023 the JEF agreed a 10-year vision and with it an ambition to be a key framework within the future European security architecture. Through this vision, and via increased political engagement, the JEF has created expectations for itself, and for UK leadership of the JEF as a European leader within NATO.

Its second decade will be far more challenging that the first. European security has dramatically deteriorated since Russia’s invasion of Ukraine in 2022. While NATO is stronger, with two new members – Finland and Sweden – and ambitious new defence plans, it is operating in a more dangerous and volatile world. Of greatest concern for Europeans is the reliability of the US security commitment to Europe under the second presidency of Donald Trump. The US faces four converging adversaries (China, Russia, Iran and North Korea) across three theatres (the Euro-Atlantic, the Indo-Pacific and the Middle East), with the capacity to prosecute only one major war. At the NATO Washington Summit in July 2024, the Alliance labelled China a “decisive enabler” of Russia’s war on Ukraine, while Iran and North Korea have been actively supplying weapons and ammunition to Russia, with North Korea in fact going further and sending an estimated 10,000 troops to counterattack Ukrainian forces in Kursk, Russia. As US priorities shift to the rise of China and its impact on Indo-Pacific security, in the coming years more will be demanded of the UK (as a leading NATO member) and the JEF to contribute to European security.

Within this geopolitical context, the JEF is at an inflection point. While it can celebrate successes over its first decade – improved interoperability, capability and capacity development, and support to Ukraine – it is yet to be seriously tested politically or operationally. There is a risk that without increased attention and resources the JEF will be unable to deliver on its self-imposed mandate, causing it to atrophy, which would amount to a serious loss of credibility for UK defence and security leadership in Europe. To avoid this outcome, it must be immediately invested in, both politically and militarily. As the new UK government undertakes its Strategic Defence Review, this paper provides recommendations for the UK to strengthen the JEF to increase its value to NATO and best contribute to European security.

Key Findings

• The JEF is a political and military power maximiser, and the UK benefits both politically and diplomatically from it – for a modest investment. The JEF provides a defence and security leadership opportunity for the UK alongside like-minded European allies and can draw on valuable military support.

• JEF members have gained increased UK defence attention and capabilities in northern Europe – which are best able to mitigate shortfalls in the event of US disengagement from Europe – and a seat at the table alongside a geopolitical heavyweight such as the UK, which assigns its nuclear forces to the defence of NATO.

• Since 2014, JEF members have delivered an average real-terms defence expenditure increase of 150%, compared to 108% for the rest of NATO’s European members. However, the UK has delivered the lowest increase. When assistance to Ukraine is measured as a percentage of GDP, while the JEF members come out on top, the UK is ranked ninth of the 10 JEF members.

• The JEF is a vanguard military grouping within NATO that provides a model for the Europeanisation of the Alliance to increase transatlantic burden-sharing. All JEF members meet or have exceeded both the NATO defence investment pledge of 2% of GDP and the guideline of 20% on equipment expenditure as a share of defence expenditure.

• Support for Ukraine has become a major political output of the JEF. The 10 JEF members have committed $11.1 billion more aid to Ukraine than the 18 remaining European NATO members. When Ukraine assistance is measured as a percentage of GDP (2021 figures), the top 10 countries include eight JEF members.

• The JEF is ideally placed to accept the increased burden-sharing that Europe is set to encounter in the coming years, especially following the war in Ukraine and Trump’s re-election.

Introduction

The Joint Expeditionary Force (JEF) is a 10-member defence framework that operates within its principal geographic area of interest of the High North, North Atlantic and Baltic Sea regions. It was born out of NATO initiatives and maintains its complementarity with the Alliance – in the sense that JEF activity and policy do not compete with or duplicate those of NATO.

In 2024, the JEF celebrated its 10-year anniversary, and it has agreed on a vision to 2033. It is a prominent, but contested, framework within the European security architecture.

The JEF has its champions (within and outside its membership and across the European security expert community) as a responsive and flexible framework that supports NATO defence and deterrence activities in northern Europe. In its first decade, it has improved interoperability, coordination and coherence across its membership and responded effectively to increased Russian aggression following the invasion of Ukraine. However, the invasion is a catalyst for a severe and potentially long deterioration in European security, and the JEF’s second decade will be much more challenging than its first. It must urgently acknowledge this and strengthen itself accordingly.

The JEF also has its detractors within NATO and within the JEF itself. The most dismissive have labelled it a post-Brexit vehicle for UK influence in Europe, despite the JEF being introduced in 2012 – three years before the Brexit referendum was first referenced (in a national security context) in the 2015 Strategic Defence and Security Review. The JEF has also been described as a regionally focused “NATO lite”, with limited value now that Finland and Sweden have joined the Alliance.

To counter this critical narrative and avoid misconceptions it is important that the JEF, led by the UK, reaffirms its value, purpose and potential to bolster European security in the future security environment. Moreover, its communications should be rebalanced towards non-member NATO allies, rather than its internal audience, to increase understanding.

As the JEF becomes more political, it is likely to fall victim to growing misperceptions. Despite its ambition and longevity, surprisingly little has been written to date on the JEF, and as such it has almost no public profile. This paper aims to clarify these misunderstandings through an analysis of the core JEF founding documents, alongside interviews with the senior UK military officers who created it and multinational officers who have developed it.

The paper argues that the JEF has several comparative advantages over other European defence and security frameworks – its political and military leadership, its flexibility, combined military heft and regional expertise – and that these are likely to become more valuable to European security as it deteriorates in the wake of Russia’s invasion of Ukraine. Furthermore, the paper argues that European security will demand more of the UK and the JEF in the future as the war in Ukraine continues and the reliability of the US security commitment to Europe is questioned under the second Trump presidency. The JEF is already under-resourced for its ambitions to be, alongside NATO, one of the “enablers of regional security”, and to operate across the whole spectrum of conflict, including “full-spectrum interventions” in its core regions and beyond. The increased level of demand will also raise the risk of the JEF underperforming, leading to a serious loss of credibility for the UK. This risk must be mitigated by an increase in attention and resources.

The new UK government has made “reconnecting” and “resetting” relations with European allies and partners central to its foreign policy. The governing Labour Party’s 2024 election manifesto states that it will “rebuild relationships with key European allies, including France and Germany, through increased defence and security co-operation … and seek new bilateral agreements and closer working with Joint Expeditionary Force partners. This will strengthen NATO and keep Britain safe”. As the JEF moves into its second decade, and as the new UK government undertakes its Strategic Defence Review (SDR), it is an opportune moment to re-evaluate and strengthen the JEF. With the risk of war in Europe increasing, the members of the JEF will have to rely on each other more heavily.

This paper provides recommendations on how to best develop the JEF to increase its value to European security. Its research is based on three questions:

1. To what extent does the JEF have comparative advantages over other European defence and security frameworks?

2. How has the JEF responded to a deteriorating European security situation since Russia’s war on Ukraine, and what might this mean for its future potential?

3. How should the JEF further adapt to deliver the most value to the UK, its membership, NATO and European security?

Methodology

The research for this paper is based on primary and secondary research. First, in June and July 2024 the author conducted a comprehensive review of the JEF policy documentation, principally its founding Memorandums of Understanding (MoUs) and policy direction, alongside joint statements following JEF meetings. This was complemented by a review of academic literature and European media reports.

Second, between June and November 2024 the author conducted 24 semi-structured interviews and consultations (in person and online) with former senior military officers who were heavily involved with the establishment and early development of the JEF, as well as serving UK military officers and civil servants. Interviews with representatives from national ministries of defence and foreign affairs of JEF members and non-JEF NATO allies provided a multinational perspective, to avoid a UK-centric analysis. All interview data has been anonymised to protect the identity of those interviewed, and where interviewees have been named, it is with their full informed consent and knowledge.

Third, the research was informed by the findings from eight expert-led data-gathering roundtable discussions focused on transatlantic security, held between April 2022 and June 2024 in London, Oslo and Washington, DC. The data gathered from these roundtables has also been anonymised.

Structure

The paper has three chapters. Chapter I identifies and assesses the advantages of the JEF and makes a comparison with other European defence and security frameworks. Chapter II examines how the JEF has responded to Russia’s war against Ukraine and the subsequent dramatic changes it has driven in European security. Chapter III considers the challenges to the UK, the JEF and European security following the war in Ukraine and the 2024 US presidential election. It provides recommendations for the new UK government for the further development of the JEF to best contribute to European security. The Conclusion argues that the UK must take the opportunity to strengthen the JEF to respond to a deteriorating security environment.

I. The JEF’s Value to European Security

This chapter assesses the value of the JEF to European security. It identifies and analyses its comparative advantages against those of other European defence and security frameworks through an examination of its design principles, origins and development from 2012 to 2021.

Origins

The JEF was born from overlapping NATO initiatives in the early 2010s. The Alliance’s International Security Assistance Force mission in Afghanistan (2003–14) and Operation Unified Protector – enforcing UN Security Council Resolutions 1970 and 1973 with regard to Libya (2011) – exposed poor European interoperability, coordination and strike, and capability and resource gaps, partly attributed to austerity effects following the 2008 financial crisis. To address these deficiencies, in 2012 NATO launched its Connected Forces Initiative (CFI) and “Smart Defence” to strengthen the Alliance and collectively drive better value for money.

In 2012, the then Chief of the Defence Staff, General David Richards, unveiled the JEF in a speech at RUSI, in which he described it as “the core of the UK’s contribution to any military action, whether NATO, coalition or independent” and as being designed to always meet NATO obligations. Russia’s annexation of Crimea and incursions into the Donbas in February 2014 provided the external drivers for the development of the JEF. The NATO Wales Summit later that year launched the Framework Nations Concept (FNC), which was an effort to formalise and enhance the CFI and Smart Defence by establishing a lead country to act as a “hub” that a group of countries could to plug into, and to set standards and drive momentum. The JEF became the UK contribution to the FNC as “a rapidly deployable force capable of conducting the full spectrum of operations, including high intensity operations. It will facilitate the efficient deployment of existing and emerging military capabilities and units”.

The JEF is, and always has been, complementary to NATO, which is a core advantage. The early adoption of NATO standards and doctrine as a baseline created a shared commonality on which to build. Following the adoption of the first NATO regional defence plans since the end of the Cold War – which incorporate and amalgamate national defence plans under Article 3 of the Washington Treaty (“individual and collective capacity to resist armed attack”) – there is a much stronger synergy between tactical, operational and strategic defence plans. Under this revised construct, therefore, stronger UK or individual JEF member defence capabilities concurrently strengthen both the JEF and NATO.

The following comparative advantages stem from the creation and early development of the JEF which, unlike most other European defence and security frameworks, has prioritised flexibility, adaptability and specialisation.

Like-Minded European Defence Heavyweights

The strategic like-mindedness of JEF members – especially regarding the Russian threat – provides the driver across several metrics for the force’s collective development as a vanguard defence force within NATO.

First, the JEF is led by the UK, which, unlike France, assigns its nuclear forces to the defence of NATO, thereby extending its nuclear deterrent to JEF member countries. This capability will become more crucial to Europe in the more “unsettled circumstances” for NATO where the US commitment to Europe is assessed as “less reliable”, particularly under the second Trump presidency.

▲ Table 1: Timeline of the JEF’s Development, 2014–24. Source: The author, based on a systematic review of the core JEF policy documentation, augmented by author interviews and media sources.

Moreover, the existence of a further decision-making centre contributes to NATO nuclear deterrence by making it harder “for Russia to use nuclear threats to deter the UK … from coming to the aid of an exposed NATO state in a crisis if Moscow knew that they had nuclear forces of their own”. This is especially valuable to JEF members, five of which border Russia, who could become increasingly exposed due to changes in US policy under Trump and Kremlin attempts to use sub-threshold means to isolate vulnerable NATO members.

Second, the JEF members collectively outspend their European allies on defence. As of 12 June 2024, all JEF members met or exceeded both the NATO defence investment pledge of 2% of GDP and the guideline of 20% on equipment expenditure as a share of defence expenditure (Iceland is not included in NATO figures, as it has no military). In addition, JEF members have delivered an average real-terms increase of 150% since 2014, compared to 108% for the rest of European NATO members, with Lithuania topping the Alliance chart with an extraordinary 327% increase.

Third, readiness is about not only percentages of defence expenditure, but also capabilities that are optimised for war. JEF members operate some of the most sophisticated military capabilities in Europe; for example, five JEF members (the UK, Norway, Finland, Netherlands and Denmark) operate F-35s, out of a total of 11 European air forces.

Fourth, they are the biggest supporters of Ukraine in the war against Russia, committing more support by value than the rest of the non-US NATO members combined (see Table 4).

While JEF members have demonstrated collective leadership on increasing defence expenditure, the UK, as the framework nation lead, has seen the lowest increase of all members since 2014. In 2014, the UK was one of only three allies to meet NATO’s 2% of GDP target and one of eight to meet the 20% guideline on equipment (only four JEF members met this in 2014). Spending analysis thus validates the original FNC construct of having only one central lead to bring allies up to the standard and “shame them” into spending more and spending better. In addition, when support to Ukraine is measured as a percentage of GDP, the UK comes ninth of the 10 JEF members. These figures suggest the UK gets a great deal out of the JEF, politically and diplomatically, as a power maximiser with minimal investment. While this approach might have been sufficient for the JEF’s first decade, the evolving – and more challenging – security environment during its second decade will not be as accommodating. If the UK wants to lead in a world that is more dangerous overall, defence spending must stretch ahead of the other JEF members, and increased investments in the JEF must be made so that it can cope with the additional demands before they arise, enabling it to operate as more than the sum of its parts.

▲ Table 2: JEF Defence Expenditure 2014–24 (2015 Prices and Exchange Rates. Source: NATO, “Defence Expenditure of NATO Countries (2014–2024)”, 17 June 2024.

The founding intent for the JEF was to become a formidable military force within Europe – which it now unarguably is. Moreover, the original FNC objective was to “improve the balance of the provision of capabilities between the United States and European Allies” or to improve transatlantic burden-sharing, where the JEF is collectively making a significant contribution. Transatlantic burden-sharing is expected to become a focal point of US policy towards Europe under the next Trump presidency, and the JEF is well placed to demonstrate what has already been achieved.

UK leadership (through the JEF and bilaterally), combined with Finland and Sweden’s accession to NATO, now makes northern Europe a political and military fortress for the Alliance that “would outrank any other European force structure and would help secure both the Eastern and Northern Flank of NATO”. Indeed, northern Europe should now be considered NATO’s “front”, rather than “flank”, as it is likely that increased NATO and Russian exercise and operational activity will be the fulcrum point for conflict between the two, through either deliberate policy or – more likely – miscalculation. Moreover, the US identifies a more accessible Arctic as a focus for strategic competition and that the US must “stand ready to meet the challenge alongside Allies and partners”.

In an interview with the author, Lord Richards said that the concept of the JEF showed prescience on the part of those within the UK system who identified the need to “think beyond Afghanistan” and recognised the growing influences of great power competition and the strategic importance of the Arctic and High North to the UK and NATO. Furthermore, Lord Houghton (Vice Chief of the Defence Staff when thinking around the JEF was initially developed, and latterly Chief of the Defence Staff when the JEF was created) confirmed that the JEF was “undoubtedly prescient”, during an interview with the author, adding that the UK saw more potential for enhancing partnerships with the Nordic and Baltic states and that the JEF “sort of worked” from the outset. Russia’s prioritisation of the Arctic and increased aggression towards Europe have validated this vision, and it was certainly prescient to invest in a flexible framework with like-minded allies who can adapt to the changing security requirements in northern Europe.

Flexibility

The JEF framework’s “flexibility by design” consists of three features: it does not require unanimity for operational deployments; it is not backed by a treaty; and it is not a standing force.

On 4 September 2014, the defence ministers of the seven founding members – Denmark, Estonia, Latvia, Lithuania, the Netherlands, Norway and the UK – signed the JEF Letter of Intent. The founding principle was that the “operational composition of the JEF will be determined by the nature of the tasks and missions it is required to undertake … and that the assignment of forces to the JEF will remain a national decision”. Unlike most other European defence frameworks, the JEF does not require unanimity to operate. Instead, an “opt-in” (also referred to as a “1+1”) mechanism preserves the primacy of sovereign national decisions and legal frameworks, with no obligation for members to contribute forces. The JEF has described the opt-in principle as a “unique advantage”.

This “come with what you can contribute” mantra was demonstrated in its first operational “test”. In 2014, when an Ebola virus epidemic spread through West Africa, European countries sent teams to assist. The UK led the European response in Sierra Leone (a former UK colony where the UK had intervened in the latter stages of a civil war in 2000 through Operation Palliser) under the JEF banner. The operation received contributions from Denmark (airlift and medical staff), the Netherlands (His Netherlands Majesty’s Ship Karel Doorman) and Norway (airlift and medical staff). The Baltic states, in order to focus on the increased Russian threat following the annexation of Crimea, chose not to contribute capabilities. This operation emphasised the deployability of the JEF, which happened in its first year and before it reached Interim Operating Capability (IOC). This contrasts with other frameworks, such as the EU Battlegroups Concept or the Combined Joint Expeditionary Force (CJEF), which have never deployed, either due to a lack of political will, an inability to make a timely decision, or a lack of military capability (see Table 3).

This flexibility makes the JEF an ideal “first responder”, able to operate with fewer constraints than NATO in sub-threshold activity below Article 4, and to “act while NATO is thinking” during Article 5 consultations at the North Atlantic Council (NAC). The 2018 MoU confirmed the JEF’s ability to deploy 10,000 troops, with supporting logistics and enablers. As a demonstration of the JEF’s ambition, a deployment of that size would be double what the EU plans to do by 2025 under the Rapid Deployment Capacity, and approximately half the size of NATO’s Allied Reaction Force (ARF – formerly the Very High Readiness Joint Task Force, which has replaced the NATO Response Force (NRF)).

The complementarity of the JEF to NATO means it should not be directly compared with NATO operational forces, but rather viewed as a valuable addition. The ARF is a rotational standing force, assigned to NATO and under the direct command and control (C2) of the Supreme Allied Commander Europe (SACEUR). Traditionally, NATO reaction forces would require a unanimous decision by the NAC to deploy. However, in 2023, the NAC delegated authority to SACEUR to deploy the ARF, significantly increasing the speed of response, and therefore becoming much more flexible and deployable in a crisis, diluting some of the JEF’s advantage in this area. This should also act as a warning to the JEF that if its comparative advantages are not maximised, they can be diminished as other frameworks adapt to the security environment. The JEF’s activity could also be viewed as being potentially less escalatory than NATO and therefore as having a wider utility. However, it is likely that such an analysis only mirrors Western views of escalation and deterrence, as there are few signs that Russia makes the distinction between the JEF and NATO, or between NATO and the US.

EU Common Security and Defence Policy (CSDP) missions similarly require the unanimity of 27 members to deploy. As a result, the EU has a poor track record of acting quickly, and it is for this reason that “Act” is the first of four pillars of the 2022 EU Strategic Compass – to remedy previous failings. Since 2007, the EU has had 18 multinational battlegroups, three of which are held at high readiness on rotation, but they have never deployed, despite the demand. However, measures to improve the ability to act, such as the introduction of qualified majority voting within the CSDP, or using Article 44.4 of the Treaty of the European Union to create EU coalitions of the willing, do not have broad political support within the EU. Either option would also require a unanimous vote for reform, and it is therefore unlikely that they would pass. Moreover, the increasing political fractiousness of the EU on foreign policy and defence could also paralyse CSDP operations in the future, as “spoilers”, such as Hungary, have a greater ability to block consensus within the EU than they do in NATO. The like-mindedness and size of the JEF mitigates this risk.

Other minilateral and bilateral European defence and security frameworks exhibit some, but not all, of the JEF’s advantages. It is unfair to directly compare some of these frameworks – such as Nordic Defence Cooperation (NORDEFCO) – to the JEF, as they are designed for a different purpose, and mutually supportive to the JEF. However, it is important to acknowledge that the JEF was the most ambitious of the three FNCs from the outset and has a higher level of ambition than other frameworks. Its collaboration within the crucial functional areas of intelligence, operations, plans and capacity development give it greater value and utility than other frameworks. This is demonstrated by the fact that it had its first operational deployment in the year it was created, before it had achieved IOC.

▲ Table 3: Comparison of European Defence and Security Frameworks Measured Against Key Criteria and NATO Defence Functions (J1–9). Source: The author, based on NATO, EU and JEF policy documents, interviews, expert commentary and open source resources.

The flexibility of the JEF offers more benefits than just operations. The JEF is a smaller and more agile framework than NATO or the EU, and these characteristics are advantageous for innovation and capability development. As a more recent addition to the European security architecture, the JEF is unconstrained by bulky legacy processes or large and unwieldy staffs. It can thus be a “a test bed for operational, doctrinal, and technical innovation”. Across the JEF members there is a wealth of experience, including in “sub-threshold competition, whole-of-government integration, and whole-society resilience”. It can create its own bespoke rules and regulations, based on the needs of its smaller membership, and “overcome long-established peacetime procurement processes which are optimised for platform-focused equipment programmes, rather than delivering agile software and technology enhancements”. Russia’s invasion of Ukraine is demonstrating the strategic importance of battlefield innovation, which NATO countries must maximise. JEF members are among the most technologically mature countries within NATO that can maximise innovation, as in the requirement resulting from the war in Ukraine. Moreover, the product of the innovation can be realised at the JEF level or, once the concept is proven, scaled to NATO level or even the EU, in a quicker timeframe through a “JEF Digital” initiative.

A Single Framework Lead

The central innovation of the FNC was to have a strong single framework lead around which the rest of the membership can coalesce. This innovation presented the UK with an opportunity to strengthen its NATO commitments, to demonstrate defence and security leadership, and to build on significant operational experience alongside European forces.

First, across operations in Afghanistan (2001–14) and Iraq (2003–11), the UK had commanded Danish, Dutch, Estonian, Lithuanian and Norwegian troops – troops from five of the seven founding members of the JEF. This hard-fought shared operational experience under UK command was too valuable to be allowed to atrophy, and the like-mindedness and cultural synergies were strong foundations to build on. Second, the UK, alongside France, led the European NATO contingent as “framework nations” in Bosnia, Kosovo and Libya, due to their expeditionary capabilities and mindset. Third, the UK had contributed to the EU Battlegroups concept since 2007, including a sovereign UK task force and a separate joint Anglo-Dutch unit. Last, the UK had strong bilateral military relationships with JEF members, such as extensive UK 3 Commando Brigade cooperation with the Norwegian military and the UK–Netherlands Amphibious Force, which has operated since 1973.

UK C2 experience and maturity is valuable to Europe. By 2015, the JEF had reached IOC with the signing of the Foundation MoU, which advanced the structure and operation of the JEF, including staffing, funding, administration and support. It also established the JEF C2 structure, with the UK’s Standing Joint Force Headquarters (SJFHQ) becoming the permanent 2* operational headquarters.

SJFHQ was created to bring the JEF together as an entity, give it an operational identity and align it more closely to NATO. In an interview with the author, Stuart Skeates, SJFHQ’s first commander, described its ambition to be a fully deployable headquarters focusing on a specific problem set and a geographically bounded area of operations. At the time, NATO had not completed the process of building its defence and deterrence strategy and so there was a gap in the sub-threshold and deterrence space that the JEF was designed to fill. Moreover, the JEF gave the option to “swing in behind the US in support of NATO” within an established C2 structure. This is particularly valuable for JEF members – which each have strong bilateral relations with the US through separate defence cooperation agreements and are committed transatlanticists – as it provides a complete and trusted mechanism to support the US independently of NATO.

This contrasts directly with the UK–France CJEF, which has developed alongside the JEF, and which is also commanded from SJFHQ. A product of the Lancaster House Treaty of 2010, it is mission specific and not a standing force. However, the CJEF has been described as “a military solution to a political problem rather than a response to military need”. The political (rather than military) logic has made the CJEF a very limited framework, and one that has also had to operate in the context of a deterioration in bilateral relations following Brexit. Moreover, its C2 structure – one UK and one French unit (battlegroup or brigade) operating alongside each other – creates military and political frictions, with no overall commander, which goes against military command logic. This is demonstrated by the fact that after 14 years, and four years since it reached FOC, the CJEF still has not deployed, despite the demand and opportunity in the Sahel (2013–22), Kabul (2021) and Khartoum (2023) evacuations, or in supporting NATO deterrence and defence activities in the Euro-Atlantic.

Regional Strength and Expertise

The Russian threat to northern Europe is severe across all domains, but is especially so in the maritime and nuclear spheres, given that the region is home to Russia’s strategic nuclear forces and its prestige Northern Fleet. The July 2022 Maritime Doctrine of the Russian Federation declared the ambition to become a “great maritime power” and identified NATO and the US as central existential threats. The Arctic is explicitly a focus for strategic competition, and the combat capabilities of the Northern Fleet have grown to meet this. With its conventional forces severely weakened in Ukraine, Russia is highly likely to use hybrid and nuclear signalling to achieve its objectives in northern Europe. Combined with growing Russia–China cooperation, and a focus on strategic competition, the Arctic is likely to be a flashpoint for a wider conflict.

The JEF’s maritime focus matches the primary Russian threat, and its regional expertise and specialisms enable it to act as a bridge between national defence plans – under Article 3 of the North Atlantic Treaty (“maintain and develop … individual and collective capacity to resist armed attack”) – and the new NATO regional plans adopted at the 2023 Vilnius Summit. Moreover, UK and JEF interests and engagement straddle the NATO regional plans for the “Atlantic and European Arctic” and “the Baltic and Central Europe”, creating greater synergies, addressing seams and handoffs between the plans, and improving mutually reinforcing responses.

The underlying defence principle of regional specialisation is as “old as NATO itself”. Regionalisation featured in the first 1949 Strategic Concept and was developed through the Cold War into five geographic regional planning groups (RPGs), which included northern Europe, so that “each nation should undertake the task, or tasks, for which it is best suited”. The 2014 FNC restated the principle of regionalisation to “work multinationally for the joint development of forces and capabilities required by the Alliance, facilitated by a framework nation … based on regional ties”. However, regionalisation is a contested concept within NATO and the “360-degree security approach” – geographically and by domain challenges – agreed at the 2016 Warsaw Summit serves a political rather than military logic, where blocs within NATO are discouraged. Here, the possibility of discord within the Alliance arises, where the JEF can be dismissed as a regional bloc or “NATO lite” within northern Europe, especially now that all members are also NATO members. However, this paper argues that the JEF has a growing value to northern Europe, and by extension NATO, and is more than the sum of its parts. However, it is ultimately the JEF’s responsibility to successfully make this argument within the Alliance.

Political Utility

The JEF has political utility for both the UK and its European members. The JEF is not just a defence framework; it has developed a significant political dimension (see Chapter II). In 2021, the JEF Policy Direction substantially advanced the JEF by establishing the strategic policy and political context. To deal with the assessed increase in strategic competition, it invited “greater political and policy input into JEF governance mechanisms”. At the time, the principal governance structures were all military – chiefs of defence, MoD permanent secretaries, and JEF defence policy and military directors’ (2*) meetings. As such, the input from member countries’ ministries of foreign affairs was minimal, as was political engagement.

For the UK, the JEF is a power maximiser and, since Brexit, it has allowed the UK to demonstrate leadership and engage with Europe on defence and security, independently of NATO in a flexible way that serves its strategic culture. For its membership, the JEF has helped successfully bind the UK closer to the continent, and northern Europe in particular, where its military and diplomatic strengths are of most value, especially given the risk of US disengagement from Europe.

The establishment and development of the JEF made it a prominent and effective responder to Russia’s invasion of Ukraine in 2022. The next chapter assesses how the JEF has responded to the war in Ukraine and the significant changes it has driven in European security.

II. The JEF’s Response to Russia’s War in Ukraine

The war in Ukraine has accelerated the JEF’s opportunity to realise its ambitions and increase its value to European security. This chapter considers how the JEF has responded to the war, within the context of NATO and UK leadership. It covers two areas of major development – the JEF’s growing political dimension and the focus on countering sub-threshold aggression in its core regions.

European Security Following Russia’s War in Ukraine

Russia’s 2022 large-scale invasion of Ukraine has shattered the European security architecture. It has driven the largest transformation of the NATO Alliance since the Cold War, including a new Strategic Concept, a new “family of defensive plans” and a significantly hardened defensive posture. Defence spending has increased to meet this ambition, with 23 allies projected to meet or exceed the NATO 2% of GDP target in 2024, up from just three in 2014.

Outside Ukraine and Russia, northern Europe has arguably experienced the most fundamental change as a result of the war. The addition of Finland and Sweden as NATO members has transformed the region as a strategic space. The Alliance’s land border with Russia has doubled and its land area of operations has expanded by 866,000 square kilometres, while its maritime presence and control in the Baltic Sea has also increased. The UK and the JEF have played a significant role. First, the UK signed political declarations with both Finland and Sweden to protect them during the NATO accession process. Mutual security guarantees of this nature are not agreed lightly, and the speed with which these were completed is testament to the JEF and the ever-closer bilateral relationships between the UK and other JEF members. Second, the JEF adopted NATO interoperability standards at its inception, giving Finland and Sweden the opportunity to come closer to NATO, and as such the JEF acted as a stepping stone into the Alliance.

For the UK, the war in Ukraine prompted a “refresh” of its defence, security and foreign policy. March 2023’s Integrated Review Refresh (IR2023) concluded that “the most pressing national security and foreign policy priority in the short-to-medium term is to address the threat posed by Russia to European security … and denying Russia any strategic benefit from its invasion”. Underpinning this ambition, the IR2023 committed the UK to “lead and galvanise where we have most value to add, giving particular priority … to the contribution we can make in northern Europe as a security actor”.

The UK, as a nuclear-armed geopolitical heavyweight with a geostrategic position in the North Atlantic, and with specialist capabilities – such as sub-sea, ISR and anti-submarine warfare (ASW) – can effectively counter Russian malign activity and act as a significant backstop to the US presence in the region. It can galvanise allies through NATO, through the JEF and bilaterally. Interviewees suggested that the format for UK engagement matters less than the substance of the agreements and how they are resourced.

The UK’s strategic prioritisation of northern Europe has naturally evolved since the early 2010s, and it is so central to UK interests that it is highly likely that this focus will be reaffirmed in the next SDR. As climate change gradually starts to link the UK’s primary and secondary “strategic areas” of the Euro-Atlantic and the Indo-Pacific, this interest will only increase. However, without a commensurate increase in resources to deal with these growing challenges, there is a risk that the gap will widen between the UK’s policy commitments and military resources, which will also have an impact on the JEF’s ability to deliver on its stated missions.

The JEF Response to the War in Ukraine

The JEF’s activity in the 18 months following the Russian invasion increased eightfold compared with the preceding eight years. This included deploying its headquarters to Iceland and the Baltic states, dispersing multinational liaison officers throughout Europe, increasing exercises, and deploying military forces to strengthen critical underwater infrastructure (CUI) protection after JEF defence ministers activated Joint Response Option (JRO) 3.2 for the first time.

However, volume of activity, rather than the effect, is a poor metric for success. The JEF’s brand and identity allow bilateral or modest cooperative activity to easily be “badged” as JEF activity, which inflates the data, making the JEF appear more active and effective than it is. What matters most is also the most difficult thing to measure: Russia’s response and reaction. Russia did react to the JRO 3.2 activation (which contributed to NATO deterrence in the region), rather than to a sole JEF activity. However, a scan of prominent Russian Telegram channels and media sources returns only very brief mentions of the JEF. Moreover, no Russian politician has referenced the JEF, and no opinion pieces have been written on it, leading to the conclusion that Russia barely notices it, or does not distinguish between the JEF and NATO.

A Distinct Political Dimension

The shock of the scale and brutality of Russia’s war against Ukraine was a catalyst to accelerate the greater political and policy input that was requested in the 2021 Policy Direction. The JEF held its first-ever leaders’ call the day after the invasion, and its first “Leaders’ Summit” within three weeks, in London, attended virtually by Ukrainian President Volodymyr Zelenskyy. The then-UK Prime Minister Boris Johnson praised the flexibility, decisiveness and value of the JEF, and, given that UK officials had thought a leaders’ meeting through the JEF as a framework was “unthinkable” before the war, this demonstrated its ability to rapidly adapt to an unprecedented security situation. Leaders’ meetings are now an annual feature of JEF governance, alongside regular meetings of national security advisers, further expanding the format outside national ministries of defence.

The increase in scope and attention creates a tension of governance. The 2018 MoU began to expand the JEF away from a defence-centric framework with the commitment to be “combined, joint and interagency by design”, with the acknowledgement that “other levers of government” and the private sector are required to address the challenge of sub-threshold competition and to “maximise JEF integrated effect”. The focus on CUI demands increased private sector input and integration, as most of the infrastructure and surveillance coverage are commercially owned. Interviewees suggested that although the JEF was set up to be interagency by design and wanted more private sector involvement, these are areas that need improvement.

To increase its effectiveness, therefore, the JEF needs to expand outside defence and become more prominent across member governments. However, if it becomes too expansive, some of its flexibility and decisiveness could be lost in the quest for cross-departmental consensus. In interviews for this paper, it was clear that there were differing views between military and diplomatic officials, with some of the latter only really engaging with the JEF from 2022 following Russia’s invasion of Ukraine. In addition, concern was raised that increased political attentiveness could directly and indirectly increase ambitions, but not necessarily resources. Official defence interviewees were already concerned about overstretched resources before the JEF tempo increased to respond to increased Russian aggression. However, it could also be argued that the JEF has already achieved a great deal with only modest and organic resourcing – proving the validity of the original logic behind its creation. This would also suggest that the power maximiser effect of the JEF is significant and that any increase in resource directed towards the JEF will also be maximised and provide a greater collective effect.

Support for Ukraine

Support for Ukraine has become a major political output of the JEF.

▲ Table 4: Comparison of JEF and European NATO Support to Ukraine by Volume of Economic, Military and Humanitarian Assistance, as of October 2024. Source: Author calculations based on the A Antezza et al., “Ukraine Support Tracker Data”, Kiel Institute for the World Economy, August 2024 (excluding Albania and North Macedonia, which are not included in the dataset).

When Ukraine assistance is measured as a percentage of GDP (2021 figures), the top 10 countries include eight JEF members. By the time of the 2024 NATO Washington Summit, 17 of the 34 G7 bilateral security agreements with Ukraine (committed to following the 2023 NATO Vilnius Summit) had been signed, eight of which are with JEF members – all ahead of the US. The final two JEF members’ agreements were both in advanced negotiation stages at the Summit.

The support for Ukraine is also qualitatively impressive. Many JEF countries have provided more critical capabilities, more quickly, and through close engagement between members. For example, Denmark and the Netherlands have led on the F-16 fighter coalition, while Sweden has donated two Saab Airborne Surveillance and Control aircraft, which will greatly enhance the F-16s’ combat ability and compound their advantages. Elsewhere, the UK has partnered with Norway on the Maritime Capability coalition and with Latvia on the Drone Capability coalition, making best use of country specialisms.

Politically, the JEF seems to operate in a similar way to its military 1+1 mechanism. The UK was the main signatory of the 2023 Tallinn Pledge – the first joint statement to fully commit to “expelling Russian forces from Ukrainian soil” – alongside nine other European countries, of which six are JEF members. Therefore the JEF can collectively apply pressure and keep each member honest on the delivery of commitments, in addition to pushing other European states to do more.

Support for Ukraine has also helped to drive intra-JEF cooperation through the previously mentioned capability coalitions and through training programmes. Operation Interflex, the UK-led military training mission for the Armed Forces of Ukraine (AFU), also supports external cooperation and political partnerships. It includes 14 countries (half of which are JEF members), including Indo-Pacific powers such as Australia and New Zealand, which share security interests in Ukraine and elsewhere.

The JEF is limited by what it can offer Ukraine militarily, outside of supplying arms and training AFU troops. The 2023 JEF Visby declaration invited Ukraine to observe JEF exercises in 2024 and 2025 so as to increase interoperability and capability development. While politically supportive, the declaration has little military utility for either side – Ukraine does not operate in the JEF core regions, has very limited maritime capabilities, and cannot share the troops. Nonetheless, Ukraine has become the crucible of wartime innovation, where the potential of the JEF as a “test bed” is significant, and this factor must be exploited as soon as possible to best prepare JEF members for a potential war against Russia.

Interviewees unanimously expressed the view that JEF support to Ukraine should remain as advocacy and as a guiding principle to galvanise commitments and increase pressure on JEF members and non-member allies to do more. They were concerned that the JEF should not adopt a more formal role, due to an already complex support architecture, through the Ramstein format, NATO and the EU – to avoid duplication and maximise effort. None of the 24 interviewees advocated for JEF membership to be extended to Ukraine.

Optimising for Sub-Threshold

The failure of Russia’s “special military operation” in Ukraine and the resulting war of attrition have severely weakened its conventional fighting power, increasing its reliance on sub-threshold aggression. Attacks and incidents on CUI (not all attributed to Russia) have already become more overt and disruptive to the functioning of NATO societies, including underwater cables between Svalbard and Norway, two Nord Stream pipelines in the Baltic Sea, and the Baltic Connector data and energy links between Finland and Estonia, where the JEF deployed a maritime task group in response.

To respond to this challenge, the JEF is reorienting towards protecting critical national infrastructure, and particularly CUI, through increased cooperation, surveillance and exercising, as an added layer of protection for its members. In December 2023, the JEF activated JRO 3.2 for the first time, which was immediately built on through the June 2024 Exercise Nordic Warden, consisting of 30 ships from the full 10 members, to intensify cooperation, increase surveillance and monitor vessels of interest in order to deter any sabotage attempts. It supported the annual NATO Baltic Operations (BALTOPS) exercise in the region, demonstrating the seamless interoperability with NATO.

While valuable, the JEF is operating in an increasingly congested space, with challenges regarding ownership, governance, legislation and duplication of effort. CUI protection is first and foremost a national prerogative under NATO’s Article 3. It is also a multinational responsibility for NATO, which has created two new organisations – the Maritime Centre for the Security of Critical Undersea Infrastructure, at its headquarters in Brussels, and the Critical Undersea Infrastructure Coordination Cell (to coordinate allied activity by bringing together military and civilian stakeholders) at its Maritime Command (MARCOM) at Northwood, UK. In addition, the EU’s resilience agenda under its Strategic Compass provides another layer, along with the EU Hybrid Toolbox (including the Hybrid Fusion Cell and new Hybrid Rapid Response Teams) and new maritime strategy and expanded directive on CUI. There is also an EU–NATO Task Force on Resilience of Critical Infrastructure. These enhancements have all occurred since the Nord Stream sabotage, despite UK officials warning of the threat five years earlier. Indeed, the 2021 Policy Direction highlights the increased demands of countering sub-threshold activity in all domains, and Exercise Joint Protector in 2021 had already started to focus more on sub-threshold interoperability. With NATO’s new military strategy and the Defence and Deterrence of the Euro-Atlantic Area, it was gradually hardening its conventional defence posture, so the JEF, to be complementary, focused on sub-threshold.

Dick Zandee and Adája Stoetman have suggested that in this contested space, the JEF should become a “gap filler” or “security bridge” between national and multinational frameworks, and between NATO and EU efforts. As the JEF is not tied to the rules and regulations of either NATO or the EU, it has more options to respond. It is also an ideal framework to civilianise the response, but it could slow the response capability of the JEF if it becomes too cross-departmental and bureaucracy increases. Zandee and Stoetman conclude that a lack of consensus makes it more important to define more clearly the roles and functions in the hybrid domain, and therefore a mission statement on the exact contribution it will make to hybrid is needed.

General Jim Morris, former commander of SJFHQ, explained during an interview that the JEF’s persistent Joint Integration Options (JIO) and proactive JROs were specifically developed to operationalise and cohere national options and responses together as “integrated military activities”. He dismissed the idea that this was merely “badging” extant or bilateral activity and argued that they have developed a genuinely cohered response and provide options for the future based on multiple scenarios. Moreover, he argued that NATO responses were linear and could only gradually move up the escalation ladder as each response was agreed and activated, but the flexibility and speed of the JEF allowed it to use JROs to provide additional deterrence effect in the right place and at the right time. This is consistent with the intent in the 2023 Defence Command Paper “to provide an additional tier of defence, security and stability” to NATO.

There are also limitations to this approach. The JEF chose not to directly respond following the Nord Stream attacks, as any response operation would have needed to include Germany because of its pipeline ownership and position as a major Baltic Sea power with 1,000 kilometres of Baltic coastline. Germany is increasing its maritime role in the Baltic Sea through hosting NATO’s Baltic Maritime Component Command (BMCC), which would make closer German and JEF maritime cooperation more important to support the JROs and JIOs. The JEF could also benefit from the growing bilateral UK and Germany defence cooperation under the Trinity House Agreement, which could enhance coordination between the UK-commanded MARCOM and SJFHQ, and Germany’s command of the BMCC.

Indeed, a major challenge for the JEF is how to operate within the Baltic Sea with Germany, and Poland, on the outside. Moreover, in April 2024, a new agreement was signed between Belgium, Denmark, Germany, the Netherlands, Norway and the UK (four of which are JEF members) to protect CUI across the North Sea countries. The fact that the signatories thought that an additional agreement was required, covering a JEF area of focus and a region in which it operates, suggests that its role is ill defined and not fully accepted in Europe. Most recently, on 17 November 2024 – while the JEF was on Exercise Joint Protector 24 in Latvia – two undersea internet cables (one between Finland and Germany and one between Sweden and Lithuania) were damaged. The Yi Peng 3, a Chinese-flagged vessel, is suspected of dragging its anchor to damage the cable, which echoes the New new Polar Bear’s actions during the 2023 Baltic Connector incident. At the time of writing, the Yi Peng 3 was anchored in international waters between Denmark and Sweden, refusing requests by the latter to move into Swedish waters to support investigators. Thus far, there has been no public statement on the JEF and no JRO activated, with individual members responding.

Shaping Strategy

The central weakness of the JEF’s role of becoming a gap filler or strategic bridge is that it is outsourcing strategy to external organisations. Moreover, those gaps are likely to change over time, providing less control over JEF development for its members. The JEF aspires to operate across the spectrum of conflict, but it is becoming squeezed at both ends as NATO returns to defence and deterrence as a priority at the higher end, while, at the other end, sub-threshold (particularly CUI protection) becomes an increasingly congested area where the JEF’s role is unclear, despite increased effort. Since the JEF’s reorientation to CUI protection, it has not dropped its objective of operating for high-intensity intervention or warfighting with a force of up to 10,000. The JEF has developed iteratively, initially with the Letter of Intent, then various MoUs, the 2021 Policy Direction and latterly the JEF vision. This has led to the JEF adding tasks, rather than making an honest appraisal of how new responsibilities have an impact on existing ones. A JEF strategy would help define its purpose, value and role better, especially to non-member allies.

In response to Russia’s war in Ukraine, the JEF now has a fully functioning political level, and operational and tactical level cooperation is delivered through the JIOs, JROs and exercising. The JEF strategic level, therefore, appears to be missing. Greater political interest in the JEF is an opportunity to better define a strategic level, especially in anticipation of demand increasing over the course of the next decade as European security deteriorates and the US leaves gaps in European capabilities in northern Europe. The next chapter explores how the JEF can further develop to meet this requirement.

III. The JEF and the Future of European Security

This chapter examines the imminent challenges to the UK and the JEF within the context of a deteriorating European security environment and uncertainty about US commitment and posture. It provides recommendations to the new UK government – as it undertakes its SDR – on how best to strengthen the JEF and increase its value to European security.

The Strategic Context

The world is becoming more dangerous and volatile, with a convergence of threats emanating from an “axis of authoritarian states” – Russia, China, Iran and North Korea – which are actively challenging the rules-based international order. These threats are becoming more interlinked, with China now designated a “decisive enabler” of Russia’s war against Ukraine, and Iran and North Korea actively supplying significant lethal aid. Russia’s war against Ukraine has shattered the European security architecture, which is experiencing its most serious crisis since the end of the Cold War, and longstanding pillars of European security are being undermined.

First, the European security architecture has gradually, and then suddenly, deteriorated, alongside a near total erosion of the arms control, disarmament and non-proliferation architecture that has contributed to strategic stability on the European continent since the Second World War. The extent of the degradation of this architecture means that a redesign, rather than reform, might be required, leading to bolder changes to tackle greater challenges.

Second, there is growing concern over the reliability of the US security commitment to Europe. President-elect Donald Trump’s public statements of ambivalence towards NATO and intention to pressure Ukraine towards negotiations with Russia are already causing concern in European capitals. Amid the convergence of threats and growing strategic power competition, the US faces four adversaries across three theatres (the Euro-Atlantic, the Middle East and the Indo-Pacific), but has the capacity to fight only one major war. US strategic interests will continue to shift towards Asia and the “pacing threat” of China, with US attention and assets in Europe following. Consequently European NATO (and Canada) will need to do far more for defence and deterrence in the Euro-Atlantic and to maintain support for Ukraine.

Third, war with Russia is a realistic possibility. NATO’s 2010 Strategic Concept stated that “the Euro-Atlantic area is at peace and the threat of a conventional attack against NATO territory is low”, whereas its 2022 version assesses that the “the Euro-Atlantic area is not at peace … and we cannot discount the possibility of an attack against Allies’ sovereignty and territorial integrity”. NATO and member state assessments of when they will be ready for war range between three and seven years.

Within this global context, the JEF is at an inflection point. It has made a growing contribution to northern European security over the past decade, but it is yet to be tested politically or militarily in a strategic crisis-management scenario. Its growing political dimension has also made the framework too big to fail, as such a failure would mean a serious loss of credibility and trust in UK leadership in Europe. To navigate the remainder of the decade, European security will demand much more from the UK and the JEF.

This is a strategic imperative, and one that the UK cannot afford to miss. And, as the new Labour government completes its SDR, it also constitutes an opportunity. UK Secretary of State for Defence John Healey has directed a “NATO first” defence policy and will apply a “NATO test” to all UK defence capabilities.

Under the new NATO defence plans and Article 3, and given the complementarity of the JEF to NATO, a “NATO test” is also a “JEF test”, and the latter should feature prominently in the SDR. The war in Ukraine has exposed the UK’s “hollowed out” forces and military deficiencies, especially in terms of readiness for high-intensity warfighting at scale. As the JEF is a power maximiser for the UK, in the short term it can provide the UK with additional diplomatic and military support to get the UK ready earlier. Indeed, the UK is already relying on NATO and JEF allies to cover critical capabilities. The Royal Fleet Auxiliary Victoria – the UK’s sole solid support ship – is to be placed on long-term layup due to a lack of trained crew, making the Royal Navy wholly reliant on allied and partner navies for logistics support to operations, with the Royal Norwegian Navy providing support to sea trials, and possibly having to provide support on the next UK carrier strike group deployment to the Indo-Pacific in 2025.

Establishing a Distinct Role in the Northern European Security Architecture

Within such a reconfiguration of European security, there is an opportunity for the JEF to establish itself fully and to more clearly define a distinct role within the security architecture of Northern Europe. To achieve this, several interviewees suggested that the JEF should ask NATO precisely what this role should be – as it derives its legitimacy from the Alliance – even if it did not necessarily like the answer. This would also have the added advantage of engaging non-member allies directly.

As a first step, the core JEF documentation should be revised, as it does not reflect the significant changes in European security brought about by Russia’s 2022 large-scale invasion of Ukraine, nor the likely future demands on the JEF. A refreshed JEF Policy Direction, MoUs and JEF vision should therefore be consolidated into an all-domain and cross-department “JEF strategy”, to include the following elements:

1. The 2021 Policy Direction states that: “The JEF is not directed towards any particular country or actor” when, just four months earlier, the UK’s Integrated Review of Security, Defence, Development and Foreign Policy had labelled Russia as the “most acute threat” to Euro-Atlantic security. Russia should be called out as the primary threat, in all domains, so as to support NATO defence and deterrence activities, align with the UK government, and mitigate the tendency in Europe towards self-deterrence.

2. The principal geographic areas of interests of the JEF are the High North, and the North Atlantic and Baltic Sea regions. The Arctic is not explicitly included, despite growing Russian military activity, growing Russia–China cooperation, and six of the JEF’s 10 members also being members of the Arctic Council (alongside the US and Russia). Including the Arctic would create greater synergy with US, NATO and UK policy, and also provide the UK with greater permission and opportunities to engage. Although US strategic interests are increasingly dominated by the “pacing threat” of China, they do not solely manifest themselves within the Indo-Pacific. The 2024 US Department of Defense Arctic Strategy relies heavily on working with allies and partners “to preserve the Arctic as a secure and stable region in which the U.S. Homeland is defended and our vital national interests are safeguarded”. Therefore, more UK and JEF engagement in the Arctic would benefit the US, and it is also an area where Europe can best keep the US engaged in European security – given the region’s centrality to US national security – and is a focal point for greater Russia–China cooperation.

3. A mission statement should be agreed, alongside NATO and the EU, that clearly defines the role of the JEF in protecting CUI and countering hybrid operations in northern Europe, alongside collaborative mechanisms to ensure all of the organisations develop in a complementary way.

4. While the JEF has more recently chosen to concentrate on sub-threshold and CUI protection, the extant policies and MoU still commit the JEF to a range of operations, including warfighting, collective defence and deterrence, and full-spectrum conflict interventions. With NATO’s hardening of its defence posture since 2022, the role of the JEF in supporting conventional deterrence and defence also needs clarification, with reference to NATO’s Article 4 (territorial integrity, political independence or security threats), Article 5 and DDA.

5. The JEF vision should be revised to become forward looking rather than reaffirming past activities and commitments, and describe what the JEF should look like in 2035, with reference to a vision statement, mission statements, a unifying purpose and significant delivery milestones.

6. The accession of Finland and Sweden to the Alliance has created a C2 headache for NATO’s command structure and a challenge in how to balance the requirements of the Nordic and Baltic states under the “Atlantic and European Arctic” (North) and the “Baltic and Central Europe” (East) NATO regional plans, with the need to be mutually reinforcing and supporting. Despite progress in this area, NATO C2 requirements are constantly evolving in response to the situation and several obstacles remain in operationalising the enlargement of the Alliance and in supporting the Nordic states to rebuild their warfighting capabilities. The UK and the US can help reduce these obstacles and maximise the opportunities of a united Nordic region within NATO. The July 2023 UK Defence Command Paper refresh stated that “as the Alliance looks to welcome in two new members, the UK will also lead the collaboration amongst Allies to shape a revised Control and Command structure, with a specific focus on Northern Europe – the regional area of greatest importance to our homeland defence”. As the NATO command structure continues to evolve, the UK’s C2 structures and maturity – both through SJFHQ and MARCOM – make it an ideal lead for any command reform across northern Europe.

7. Duplication of JEF activity should be deconflicted and removed from that of the Northern Group of Defence Ministers. A process for both frameworks to work better together, alongside Nordic Defence Cooperation, should be designed.

The JEF and the Europeanisation of NATO

Europeans stepping up on Euro-Atlantic security is often referred to as the “Europeanisation” or “European pillar” of NATO. However, this concept is ill-defined among allies, with little consensus in Europe on the scale, pace and methods required, despite the obvious need.129 While Europe as a whole is deciding what to do and what approach to take, the JEF can lead by example, as a vanguard force within the Alliance, in further augmenting European defence. As articulated in Chapter I, the JEF’s distinct advantages and military strengths provide a model for the Europeanisation of NATO and can guide the process in three ways:

1. As a strong politico-military regional bloc within NATO which provides a serious offer to defence and deterrence, alongside transatlantic burden-sharing.

2. As a united “pressure group” within NATO to push itself and other allies to increase defence spending, increase readiness, invest in critical capabilities, and be stronger and more united in dealing with Russian aggression.

3. As a model for other groups of states to replicate regionally.

Europeanisation involves more than just military capabilities. NATO currently operates a “360-degree” security approach – the belief that all allies should be able to operate in all regions and all domains – but this is only possible when backed by strong US leadership. If the US disengages, no single European power, or groups, can fill the vacuum. Therefore, an update to the RPG model and increased regionalisation might be the only way to keep NATO together in a configuration that is close to its current form. This would work best in northern Europe, due to the challenging operating environment, and, rather than undermine the 360-degree approach, increased regionalisation could be a strength. The JEF is an ideal model and there are options to replicate it geographically and thematically within Europe, provided countries step up to lead new groupings. This process would further inform the tasks to which the JEF should commit in northern Europe.

JEF Military Tasks in Northern Europe

The JEF can provide more value to the UK, the US and NATO in northern Europe by seeking inspiration from NATO’s 1949 Strategic Concept and the direction that “each nation should undertake the task, or tasks, for which it is best suited … while certain nations, because of geographic location or because of their capabilities, will appropriate specific missions”. The JEF should offer itself up to NATO and the US as a strategic enabler in four areas:

1. NATO’s 2022 Strategic Concept states: “In the High North, Russia’s capability to disrupt Allied reinforcements and freedom of navigation across the North Atlantic is a strategic challenge to the Alliance”. As a warming climate opens the Northern Sea Route and links the Euro-Atlantic to the Indo-Pacific, there will be significant economic potential for Europe. The US and Canada, which already have Asia-facing ports and routes via the Northwest Passage and the Pacific Ocean, have little incentive to provide sea lines of communication (SLOCs) protection and freedom of navigation operations for the economic benefit of Europe. The JEF should accept this mission on behalf of Europe.

2. JEF members are the primary beneficiaries of US transatlantic reinforcements. All Nordic and Baltic national defence plans can be summarised as fighting the “first battle” and holding Russian forces until US reinforcements arrive. It is also highly likely that any UK strategic reserve will fight on JEF territory. The UK’s strategic position within the North Atlantic and its theatre ASW capabilities make it a key enabler of transatlantic reinforcement. Therefore, the assurance of NATO’s transatlantic reinforcement plan could be a specific offer the JEF could make to the Alliance and the US, making a significant contribution to burden sharing and NATO defence planning, and ensuring that the US is further tied to northern Europe.

3. The JEF should commit to persistent operations in its core regions and move from exercises to mission rehearsals, using live intelligence, situational awareness and greater connectivity that can scale to the immediate threat, instead of annual “set piece” exercises, such as the Joint Protector series. Russia is persistently operating in all domains against northern Europe. As any of these incidents could quickly escalate into an Article 4 or 5 situation, and as this is precisely where the JEF’s flexibility is a main advantage, it needs to be able to scale at a moment’s notice. While the JEF focus might be on CUI protection, it still aspires to operate across the spectrum of conflict and therefore it should rehearse conventional deployments, in credible strength, to have a real deterrence effect. This should include an increased ability to conduct information operations to create coherence across JEF members to counter Russia.

4. A changing climate may necessitate future humanitarian assistance, disaster response and search-and-rescue operations. Delivering coordinated activity as a first responder under a JEF banner could be beneficial and follow the model of the 2014 Sierra Leone intervention. The House of Commons Defence Committee in 2023 described the requirement as follows:

The increasing exploitation of the Arctic for international trade and exploration for critical minerals gives greater importance to the role of the Joint Expeditionary Force (JEF) as a security alliance in the “High North”. The Ministry of Defence should assess how the JEF might need to be adapted in the face of climate-change induced developments in the Arctic and beyond.

At the time of writing, the US President-elect is assembling his top team. While his nominees still require Senate confirmation, some immediate reactions in Europe have characterised the process as “terrifying”, and the reliability of the US commitment to European security is openly being questioned.

In this context, the importance of the JEF increases for several reasons. First, the JEF as a vanguard military force within NATO can mitigate the loss of some US military capabilities and enablers that underpin deterrence in northern Europe. Second, as leading military spenders in NATO and the biggest supporters of Ukraine, JEF members can collectively pressure allies to increase defence spending and support to Ukraine. Third, the JEF collectively, with the UK in the lead, is well placed to try to convince Trump of the value of European security to the US. The JEF – using the standing of the UK–US bilateral relationship and a new NATO Secretary General, Mark Rutte (a previous prime minister of a JEF member since its inception, and a widely reported “Trump whisperer”) – can help counter the narrative of European free riding, prevalent in the modern US Republican Party, through demonstrating its commitment to collective defence spending and support to Ukraine.

Governance and Resourcing

As the JEF becomes more political, it will become more unwieldy and could lose some of its flexibility and quick response benefits. To mitigate a “turf war” between Downing Street, the MoD, the Foreign, Commonwealth & Development Office and the Cabinet Office, the JEF should proactively establish an agreed governance structure across Whitehall. The purpose of this would be to ensure that political and policy aims do not stretch the JEF military resources too far and widen the gap between expectations and reality. Greater involvement from the UK intelligence community should be sought to create a “10 EYES” intelligence partnership. Now that Finland and Sweden have unrestricted access to NATO Secret classified intelligence and above, this opens the door to greater collaboration, putting the UK at the heart of a global “JEFEYES” intelligence network. This would also create a significant redundancy in the event that Trump follows through with this threat to cut back intelligence sharing with Europe.

In its first decade, the JEF has increased interoperability, coordination and coherence between its members, despite its modest resources. In each of the JEF members, there are only a handful of full-time military and official staff, split between policy and operational (HQ) roles. This includes in the UK (as the framework lead), where posts are split between security policy and SJFHQ, with liaison officers supplied by JEF members to the latter, making the JEF operational side better resourced than the security policy side, leading to an imbalance and an underdeveloped policy dimension. In terms of costs, the UK funds JEF operational activity, governance and administration, as outlined in the 2018 Comprehensive Memoradum of Understanding (CMOU), with JEF members meeting their own costs. Schedule 13.4 of the 2018 CMOU grants JEF members the ability to “share the costs of particular activities” defined by “the activity, national contributions and cost-sharing arrangements”. While this might have been sufficient until now, it is likely that it will not be sustainable in the future as greater demands are made of the JEF and as its ambitions increase. However, as a power maximiser, even modest increases in resources are likely to have a disproportionately large effect.

Increased funding should prioritise reinforcing the JEF Secretariat, with additional staff drawn from JEF members. This would also be an opportunity to gain greater industry, private sector and academia involvement to make the most of the JEF innovation potential and gain quick momentum on initiatives. Furthermore, the UK MoD should look to JEF member countries to lead on any commissioned initiatives, such as a “JEF bank” or “JEF Digital”, if there is limited capacity within its own system; this could become a powerful development tool.

Increase Partnerships

Interviewees were unanimous that the JEF had an “optimal membership” and thought that enlarging the membership, especially to a larger European state such as Germany or Poland, would dilute the JEF’s advantages too much. Instead, it was suggested that the JEF should increase partnerships and external engagement to prevent the “inside–outside” dynamic that exists within NATO. These partnerships should prioritise agreeing “plug-in options” whereby other countries can benefit from the flexibility of the JEF and contribute to certain missions, exercises and activities based on the situation and threat.

The priorities for enhanced partnerships are Germany and Poland, due to their prominence within NATO and the EU and their key roles within Baltic Sea security and forward land forces on NATO’s eastern front, which, at a minimum, would benefit from increased deconfliction from JEF activity. Next, partnerships with the US and Canada should focus on providing High North security and SLOCs protection, and on assuring NATO’s transatlantic reinforcement plan in crisis and conflict.

There is growing concern over Russian activity in the Irish Sea, including naval exercises in Irish waters, and the vulnerabilities this poses to Euro-Atlantic security, particularly CUI, with its significant concentration of undersea internet cables that network out to northern Europe. Given the geographical importance of the Republic of Ireland, the UK should also encourage greater engagement between the Republic of Ireland and the JEF on CUI protection, which could help manage the sensitivities surrounding Irish neutrality in a similar fashion to Sweden and Finland joining the JEF in 2017 while non-NATO members.

The JEF can also make better use of UK partnerships. As an example, AUKUS recently developed an improved algorithm for its trilateral interoperability of the P8 maritime patrol aircraft, and its members are also planning to integrate UK Sting Ray torpedoes onto the airframe. The UK, the US and Norway operate a similar P8 trilateral operation in the North Atlantic, and this technological improvement could be extended to Norway and thereby increase ASW capabilities and improve the collective ability to counter emerging maritime threats. Furthermore, the growing UK–Japan relationship could help increase links with the JEF, which would be less contentious than doing so through NATO, which has been unable to agree on establishing a liaison office in Japan. The relationship between Japan and JEF countries will become more important as the Northern Sea Route becomes increasingly viable.

Innovation

The JEF should maximise its innovation potential by creating a JEF Digital innovation and experimentation hub. Increasing the speed of adoption and value for money in defence software development would be a technological continuation of the CFI and Smart Defence initiatives.

The new head of the British Army has emphasised the critical importance of software, in conjunction with hardware, to creating a “hybrid” system to transform from old to new ways of future warfare. He has spoken of emulating lessons from the battlefield in Ukraine, where the power and pace of technological innovation is significant, with tactical innovation cycles measured in weeks and in which Ukraine has unrivalled experience. As a result, the JEF could boost its own innovation and create more “wartime urgency” through advanced partnerships with Ukraine.

A specific early area of focus should be in maritime uncrewed surface and underwater vessels, where Ukraine has achieved the “functional defeat” of the Russian navy in the Black Sea without operating a conventional navy of its own. Lessons of this nature could be a potent addition to the JEF’s arsenal in the Baltic Sea. The JEF should do this through the recently established NATO–Ukraine Joint Analysis Training and Education Centre so as to prevent duplication and make more effective use of existing mechanisms. In addition, the JEF should extend its innovation to adopt original funding mechanisms to pay for the above enhancements through a defence finance fund (a “JEF bank”) modelled on a multilateral lending institution.

Conclusion

Throughout its first decade, the JEF has proven itself to be a valuable addition to the European security architecture, most clearly demonstrated in three areas.

First, the JEF member states have remilitarised quicker and further than the rest of Europe, and the JEF has evolved into a heavyweight military force within NATO, which is increasingly capable of responding to the Russian threat. Second, it supported the swift integration of Finland and Sweden into NATO through political support and the adoption of Alliance interoperability standards as baselines, creating a valuable stepping stone to membership. Third, it has led on diplomatic, military, economic and humanitarian support for Ukraine and has galvanised its membership, and the rest of Europe, to do more. Northern Europe is now a transformed strategic environment compared with 2014.

However, the second decade of the JEF will be far more challenging as European security deteriorates following Russia’s invasion of Ukraine. The Arctic is quickly becoming the fulcrum of strategic competition and is the area where Russia–China cooperation is most advanced. The re-election of President Trump will create a huge amount of uncertainty over the future of Ukraine and NATO’s ability to successfully defend and deter against increased Russian aggression. Consequently the demands on Europeans to step up and rebalance the burden of upholding Euro-Atlantic security will grow rapidly. While Europeans debate exactly how to do this, the JEF is already prepared, and should anticipate the incoming increase in demand by consciously stepping forward to shoulder more of the burden.

Within this rebalancing of European security, there is an opportunity for the UK and the JEF to show leadership and set the pace – and standard – for the Europeanisation of NATO. The UK SDR process should therefore examine the value and role of the JEF – in support of NATO – and use it as a power maximiser for the UK and the JEF’s other members. A comprehensive cross-department and all-domain JEF strategy would enable it to be set on the right path for the next decade and the JEF’s future should be viewed as a whole-of-government cooperative mechanism. The JEF, alongside the UK’s nuclear capability, should be a central pillar of the UK’s contribution to NATO defence and deterrence and European security more broadly. Now is the time to meet its original intent – delivered in the 2012 RUSI speech – to be “the core of the UK’s contribution to any military action, whether NATO, coalition or independent”. Moreover, Ukraine has shown the need for defence procurement to be hastened and to significantly increase interoperability, and the JEF is the most productive vehicle to harness member comparative strengths and innovation. However, its funding and resourcing must be increased so that the JEF can prepare for the additional demand placed on it in a deteriorating Euro-Atlantic security environment. If the UK misses this opportunity, there will be a growing risk that the JEF fails to live up to its ambitions, leading to a serious loss of UK leadership and credibility within Europe.

Ed Arnold is a Senior Research Fellow for European Security within the International Security department at RUSI. His experience covers defence, intelligence, counter-terrorism and counter-insurgency, within the public and private sector. His primary research focus is on the transformation of European security following Russia’s war on Ukraine. Specifically, he covers the evolving Euro-Atlantic security architecture, the security of northern Europe, and the UK contribution to European security through NATO, the Joint Expeditionary Force, and other fora.