The United Kingdom’s Defence Dilemma: Between European Security and Political Ambiguity

The views expressed are those of the author and do not necessarily reflect the position of the NOTIONES project.

The United Kingdom currently finds itself in a complex and at times ambiguous position regarding a potential defence arrangement with the European Union. This comes at a moment when the Russian threat and the ongoing war in Ukraine continue to reshape Europe’s security landscape. While many UK officials acknowledge the seriousness of the challenges posed by Russia – and, more recently, concerns related to Iran – some observers argue that internal political divisions and a lack of strategic coherence may be hindering the development of a clear and coordinated response.

From the perspective of several government representatives, there is recognition that the EU has advanced its defence thinking, particularly through initiatives such as the SAFE strategy. These developments are viewed in London as meaningful steps toward strengthening European security. At the same time, however, there is a perception that the UK has struggled to translate this strategic awareness into practical cooperation.

Officials note that the EU’s security concerns are legitimate, and some point to the particular weight of French warnings regarding Russia’s trajectory. Yet the UK has not engaged as constructively as it could with France and Germany – the two key actors shaping defence discussions within the EU. As a result, some analysts warn that the EU may be moving forward without a strong British voice, potentially reducing the UK’s ability to influence the emerging European defence framework.

This situation is compounded by divisions within the UK Parliament. Certain political factions argue for distancing the UK from broader defence integration, favouring instead bilateral agreements. Others maintain that NATO should remain the primary vehicle for responding to current threats, suggesting that the alliance itself should be adapted rather than creating new European structures.

At the same time, there is growing interest in London in exploring deeper engagement with PESCO as a third‑country participant. While this is seen by some analysts as a promising avenue, it is widely acknowledged that such engagement would not provide a quick or comprehensive solution to Europe’s structural defence challenges. Proposals for a “coalition of the willing” are also circulating, though its potential mandate and objectives remain uncertain.

Interestingly, several officials suggest that public opinion in the UK may be more open to enhanced defence cooperation than the government currently assumes. The Russian threat is widely perceived as serious and immediate, creating a gap between public expectations and political action. This gap is further complicated by shifts in the United States’ strategic posture, including its recent actions in the Middle East and Latin America. Some policymakers express concern that US support for European defence could be becoming more transactional, and that Europe may need to accelerate efforts to strengthen its own capabilities.

For decades, UK defence planning has been shaped by the assumption of consistent US backing. That assumption is now being questioned. Several voices in government circles have raised the possibility that the traditional transatlantic security model may be undergoing change. Even a future change in US leadership is not universally seen as a guarantee of renewed long‑term commitment, as earlier administrations had already signalled a desire for Europe to assume greater responsibility for its own security.

One of the central challenges identified by UK officials is the difficulty of turning strategic ideas into operational reality. This includes securing adequate budgets, building effective military structures, and avoiding duplication. Some experts argue that existing EU and NATO frameworks may not yet be sufficiently robust to confront the full spectrum of threats, pointing to the need for more formalised and integrated command structures. No European country, they argue, can realistically address these challenges alone.

The war in Ukraine is widely seen as having bought Europe valuable time to strengthen its defence posture. However, several analysts caution that a sudden ceasefire could rapidly increase pressure on European governments, raising questions about whether the necessary infrastructure and capabilities could be developed quickly enough. While the list of defence needs is long, many officials believe it remains achievable – provided there is stronger political leadership and clearer consensus.

Finally, while Russia is viewed as the most immediate threat, it is not the only one. A future European defence strategy will need to address a broader range of risks, including cyberattacks on critical infrastructure and potential nuclear threats from states such as Iran. The experience of Ukraine has demonstrated that the protection of civilian and strategic infrastructure is essential for maintaining both defensive and offensive capabilities. Building resilience requires systematic cooperation, data exchange, private‑sector involvement, and stronger societal preparedness.

Author(s): Paula Gomila Marqués, Senior Researcher, Policy Adviser & Project Manager , SAHER Europe