Report from workshop in Stockholm on April 21, 2026
Summary
The transatlantic environment is changing rapidly, making the question of a stronger Europe in NATO increasingly urgent and concrete. The U.S. administration has clearly called on Europe to take greater responsibility for its own security, while the United States has stated that it intends to continue playing a central role in strategic deterrence, including nuclear deterrence.
The question is no longer whether Europe needs to assume greater responsibility, but how this can be done without weakening NATO’s deterrence and defence posture or its political cohesion. The need to act is urgent. Europe has a time-limited window to scale up while the United States still maintains a substantial military presence in Europe and while Russia remains tied down by the war in Ukraine.
The United States is facing strategic overstretch and growing demands from other regions, while the administration has contributed to political uncertainty. This means Europe must prepare for a situation in which U.S. support may be delayed, more limited, and less predictable.
A stronger Europe in NATO therefore requires combat-capable units, higher readiness, improved mobilisation capacity, integrated multinational formations, stronger command structures, and a clearer defence-industrial base.
The political dimension is nevertheless decisive. European rearmament requires public buy-in, clearer strategic communication, and broader engagement with the U.S. political environment, especially Congress. For Sweden, this development entails both a responsibility and an opportunity to strengthen deterrence in Northern Europe, help keep the United States engaged, serve as a bridge between the EU and NATO, and continue to be a clear voice for Ukraine.
Introduction
On April 21, 2026, the Atlantic Council’s Northern Europe Office and the Swedish Ministry for Foreign Affairs jointly hosted a workshop at the Government Offices in Stockholm focused on a stronger Europe in NATO and the way forward. The workshop brought together officials from the Government Offices, members of parliament, and Swedish experts, while the speakers were invited international experts. The aim was to analyse what a stronger Europe in NATO means in practice, how European allies can assume greater responsibility without weakening Alliance cohesion, and what role Sweden can play in a more Europe-oriented NATO. The discussion, held under the Chatham House Rule, focused on three key areas:
- Strategic responsibility-shifting in NATO
- European responsibility in practice
- Political cohesion, the role of the United States, and Sweden’s contribution
The following report outlines the main points of the discussion according to these three areas.
Strategic responsibility-shifting in NATO
NATO is undergoing a strategic transformation shaped by changing U.S. priorities, a persistent Russian threat, and growing demands for European responsibility. Participants noted that the Alliance is experiencing one of its most far-reaching changes since its founding.
Developments are moving toward a new division of labour, in which the United States expects Europe to assume primary responsibility for conventional deterrence and defence, while the United States continues to be responsible for nuclear deterrence and provides selected strategic enablers. This shift is driven not only by U.S. demands for fair burden-sharing, but also by Russia’s full-scale war against Ukraine, which means that high-intensity warfare is once again taking place in Europe. The war has also highlighted Europe’s dependence on U.S. capabilities, while U.S. global overstretch has increased.
A recurring theme was that Europe has a time-limited window for action. The United States is still militarily present in Europe, Russia is tied down by the war in Ukraine, and key U.S. capabilities remain on the continent. However, this window may narrow quickly, depending on U.S. political decisions on withdrawal or global crises that change how U.S. resources are prioritised.
At the same time, participants emphasised that the transition still lacks a clear end-state. Concepts such as a stronger Europe in NATO, primary European responsibility, and limited U.S. conventional support are used increasingly often, but their operational meaning remains unclear. NATO’s defence planning process was highlighted as central to defining which capabilities Europe should provide, which capabilities the United States must retain in Europe, and how quickly this shift in responsibility can take place without creating gaps in deterrence. Planning is also affected by a lack of clarity about which U.S. capabilities will actually be available, making it more difficult for European allies to determine what they themselves need to prioritise.
Sweden’s position is affected by this transition. Sweden has become a NATO ally at the same time as NATO itself is undergoing a fundamental transformation. In a short period of time, Swedish defence planning has moved from a primarily national territorial defence posture to a regional and collective Alliance defence framework. Sweden has quickly integrated into NATO structures and already contributes through its geography, its role in Northern Europe, and its participation in the Alliance’s forward presence, mainly in Finland and Latvia.
European responsibility in practice
Greater European responsibility requires both military capability and organisational coordination. The discussion showed that the issue is not only higher defence spending, but also how European allies organise, integrate, and use military power. The central challenge was assessed to be the creation of usable and integrated combat power.
Europe already has a large number of multinational headquarters, formats, and initiatives, but these are often fragmented, dispersed, and still closely tied to national structures. The next step was therefore assessed to be integration rather than expansion alone. On land, this means stronger multinational army-level headquarters, better links between divisions and higher levels of command, and the ability to command operations at scale. In the air domain, larger composite air strike forces are required, while at sea Europe needs more standing maritime presence, particularly for sustained control in the North Atlantic and the broader northern theatre.
In this context, the importance of being able to act first in a crisis or war, a so-called “first responder” capability, was also emphasised. Europe, and especially regional allies in Northern Europe, must be able to act immediately in a crisis. U.S. presence remains important, not least as a political signal and military threshold. The greater uncertainty concerns the reinforcements expected to arrive across the Atlantic. If a capability is essential for national or regional defence, European allies should therefore plan to procure it themselves, develop an equivalent effect, or create alternative solutions.
At the same time, participants stressed that Europe should not seek to replace the United States directly. Even with stronger conventional forces, dependence on U.S. strategic enablers will remain for the foreseeable future. This includes C4ISR, meaning command, control, communications, computers, intelligence, surveillance, and reconnaissance, as well as logistics, cyber, space-based capabilities, missile defence, air superiority, and long-range strike. This dependence is also organisational and political, since the United States provides strategic direction, cohesive leadership, and a structure that has historically made NATO effective.
The speakers therefore highlighted the need for clearer European operational concepts. Europe should not merely try to replace individual U.S. capabilities, but build on European strengths in a broader sense, such as economic security, sanctions, trade policy instruments, and cyber capabilities.
European rearmament was discussed as a parallel but longer-term process. While the Europeanisation of NATO is a short- to medium-term issue, rebuilding Europe’s defence-industrial base is a medium- to long-term task. Participants emphasised that the previous trade-off between buying off-the-shelf systems for rapid effect and building European industrial capacity has become less clear-cut. A stronger European defence industry also benefits the United States and NATO as a whole, since U.S. production cannot meet all global needs simultaneously.
Ukraine was highlighted as an important part of future capability development. The country has demonstrated the importance of mass, rapid adaptation, and industrial innovation in war. Ukraine cannot replace broader European or U.S. capability development, but its experience and production capacity can play an important role in certain areas. At the same time, it was noted that Ukraine already functions as Europe’s de facto first line of defence by tying down a large share of Russia’s military attention and resources.
For Northern Europe and Sweden, the military conclusions are clear. Russia remains the most significant threat to the Euro-Atlantic area, and its strategic ambitions have not changed. Sweden can contribute to stronger deterrence in Northern Europe through regional readiness, sustained presence, rapid reaction capacity, and a more coherent defence posture across the northern flank. Critical capabilities include missile defence, long-range strike, space-, satellite- and cyber-enabled capabilities, and new technologies. Through its geography, defence-industrial base, and innovation capacity, Sweden can contribute both to regional deterrence and to the Alliance’s broader capability development.
Political cohesion, the role of the United States, and Sweden’s contribution
A stronger Europe in NATO also raises political questions. The discussion showed that responsibility-shifting requires cohesion, legitimacy, and strategic communication if it is to strengthen the Alliance.
The issue of leadership was identified as central. As the United States leads less actively, Europe’s internal differences become more visible. There is no obvious European state that can replace the U.S. role, since no single European ally combines sufficient military capability, financial weight, strategic culture, and political legitimacy to take over uncontested as the Alliance’s leading power. Differences also remain between east and west, north and south, and between different threat perceptions and levels of risk tolerance.
An important tension was identified between two different ways of thinking about the need for greater European responsibility in NATO. For some allies, the point is to show the United States that Europe is taking responsibility and thereby encourage it to remain in the Alliance. For others, it is more about preparing for a scenario in which U.S. engagement decreases. These approaches can partly be reconciled, but they create different priorities in planning, communication, and investment.
Participants stressed that the U.S. challenge is not only about absence or withdrawal. A third scenario is that the United States remains formally engaged in NATO but uses its position to influence the Alliance’s political direction or complicate joint decision-making. This was linked to the U.S. security strategy’s emphasis on Europe assuming primary responsibility for its own security, but also to its broader political ambition to influence Europe’s development. Under such an approach, U.S. engagement could become more transactional and conditional on both European burden-sharing and Europe’s political development. This could affect crisis management, planning, and political unity even without a formal U.S. withdrawal, strengthening the need for European planning capacity, institutional resilience, and minilateral formats.
Keeping the United States engaged requires broader political work than traditional military contacts. Participants emphasised the need for recurring dialogue with different parts of the U.S. political environment, especially Congress. A new generation of U.S. policymakers does not have the same historical attachment to NATO or the Second World War. European countries therefore need to demonstrate more clearly why a U.S. presence in Europe serves U.S. interests, including industrial cooperation, supply chains, innovation, economic security, and the links between Europe, the Middle East, and the Asia-Pacific region in terms of military power projection. In this context, participants also discussed the possibility that European allies could finance or lease certain U.S. strategic enablers in order to raise the costs of a U.S. withdrawal while giving Europe greater predictability.
Public buy-in was also assessed to be essential. European rearmament is not only about equipment, but also about people, recruitment, resilience, and budget priorities. Without a clear public mandate, defence investments risk becoming vulnerable to political shifts and disinformation. Sweden, Finland, and the Baltic states were highlighted as countries that have come further in building national understanding of the threat environment and the trade-offs required.
Against this background, the need for clearer strategic communication was emphasised. The public debate on the Europeanisation of NATO is often unclear and risks making divisions among allies visible. This can harm deterrence by giving adversaries the impression of uncertainty and weak cohesion. Europeanisation therefore needs to be communicated as a way to strengthen NATO and the transatlantic link.
Ukraine was a recurring theme throughout the discussion. A strong and resilient Ukraine was described as one of the most important signals to Russia. At the same time, there is a difficult balance between recognising Ukraine’s role as Europe’s de facto first line of defence and avoiding a formalisation that risks creating further tensions between European allies and the United States. Participants emphasised the importance of continued support for Ukraine and of preserving Alliance unity.
Sweden has several possible roles in this context. First, Sweden can help strengthen deterrence in Northern Europe, build the ability to act as a “first responder”, and develop advanced technology together with allies. Second, Sweden can help keep the United States engaged through more proactive transatlantic dialogue, concrete proposals, and contacts with U.S. institutions, members of Congress, companies, and think tanks. Third, Sweden can serve as a bridge between the EU and NATO, especially on defence-industrial cooperation, new technologies, and supply chains. Sweden has credibility as both a European and transatlantic actor and can help reduce friction between the EU’s defence-industrial agenda and NATO’s operational needs. Fourth, Sweden should continue to be a clear voice for Ukraine and support a long-term European security solution in which Ukraine is fully included.
Conclusion
Overall, the discussion showed that a stronger Europe in NATO should be understood as a reinforcement of the Alliance and the transatlantic link. For the transition to succeed, it requires combat-capable units and capabilities, higher readiness, industrial capacity, public buy-in, and a deliberate strategy to keep the United States engaged. For Sweden, as a new ally, this entails both a responsibility and an opportunity to help shape the European pillar in NATO, particularly in Northern Europe.