Not surprisingly, British Prime Minister Keir Starmer is facing an extremely difficult political landscape in which he must manage a deeply complex balancing act. His backing of more EU defense expenditures demonstrates his commitment to European defense yet his cautious stance toward President Trump’s mercurial strategy reveals the problems in Britain’s transatlantic relationships.

From one perspective, he acknowledges the requirement to strengthen NATO deterrence because Europe remains at risk from Russian aggression. At the same time, he must realize that Trump’s transactional foreign policy focuses more on economic leverage than on military commitments which could leave Europe vulnerable when it needs protection the most. 

The choice for Starmer is not merely which side to take — Europe or the U.S. — but rather how to position Britain in the security architecture of the world after Brexit. Starmer knows that Ukraine cannot be defended by Europe on its own, especially with the deep fissures in the EU over how to share the financial and military burden. Yet, the Trump administration’s plan to prevent Russian aggression in Ukraine through corporate interests fails to qualify as serious defense policy because it is “corporate pragmatism” and “economic opportunism” pretending to be strategic thinking.

Starmer’s situation is aggravated by the fact that he must work in an environment where his domestic agenda, including restoring the United Kingdom’s economy and tackling post-Brexit trade issues, is in competition with foreign policy imperatives. It appears that Trump’s unpredictability and his disdain for multilateralism has forced Starmer into a defensive diplomatic stance, where he is more of a reactor than a shaper of events.

His interaction with Trump reveals an effort at pragmatism, but pragmatism alone is not a strategy. If Trump continues to push forward with isolationist tendencies, Britain will be left scrambling for security arrangements that do not yet exist.

This is why French and German leaders, among others, are growing increasingly uncomfortable with U.S. disengagement from NATO, which is why the recent EU move to relax deficit rules and increase military spending is significant. Starmer supports this shift, though he has to accept that Britain is outside the EU’s defense structures. 

Brexit has put the U.K. in an awkward position: still part of Europe’s security framework, but without a seat at the table in EU defense policy. While NATO remains the main platform of transatlantic defense, a hesitant and divided U.S. leaves Europe wondering if it can rely on Washington.

The Trump administration’s policy toward Ukraine — forcing Kyiv into economic concessions while eschewing military commitments — has made it difficult for Starmer to craft a coherent policy. The objective of forming a European-led security force is logical, but without U.S. support, it will be viewed as more declaratory than operational.

Starmer correctly stated that any European military intervention in Ukraine requires reliable protection assurance — yet Trump continues to undermine this goal. European leaders including Starmer need to tread carefully through an uncertain environment that Trump created by delivering vague promises alongside erratic policy actions.

Starmer is also under considerable domestic strain. There is still a division within the Conservative Party over the extent to which the U.K. should be reintegrated with European defense structures, not least because of post-Brexit sensitivities. Within Labor, some advocate for closer military ties with the EU, while others are against any measures that may be seen as a threat to the U.K.’s sovereignty. The Labor leader needs to unite his internal forces while establishing a clear security plan which maintains domestic and global support.

The broader question remains: Can Europe create a sustainable security system that does not need to rely on the United States? The EU’s recent commitments suggest an awareness that relying on Washington is no longer viable. The efforts to increase military spending might stay fragmented because Europe lacks a unified defense policy. The challenge for Starmer is to make Britain a central force in European security without being seen as a client state of either Brussels or Washington.

The central problem of Starmer’s dilemma emerges from changing global power equation. The post-Cold War system that had the United States offering security protection to Europe while Europe concentrated on economic unification has started to disappear. The transactional nature of Trump’s foreign policy has marked a departure from the longstanding bipartisan American support for NATO.

European leaders including Starmer must now face difficult truths since they need to plan for an era where U.S. backing will be unreliable or non-existent. Starmer’s efforts to maintain close ties with both Trump and the EU expose the contradictions of Britain’s strategic position. His attempt to be a bridge between Europe and America is complicated by the fact that the two sides are drifting apart. 

Trump’s skepticism of NATO and his focus on economic deals over security commitments clash with Europe’s growing sense of strategic autonomy. Starmer’s challenge is not just to manage these tensions but to define a clear and realistic British foreign policy that acknowledges the changing nature of transatlantic relations.

The stakes are high. If Starmer fails to secure a credible defense arrangement, Britain risks being caught in a security vacuum, neither fully integrated with European defense efforts nor assured of U.S. support. His efforts to balance competing interests — Trump’s America First doctrine and Europe’s push for greater military independence and strategic autonomy —  underscore the precarious nature of Britain’s geopolitical position.

Ultimately, Starmer’s diplomatic balancing act reflects the broader uncertainty facing Europe. With an unpredictable U.S. partner and a Europe still struggling to define its own security role, Britain must make hard choices. Straddling both sides may no longer be feasible. The question is whether Starmer will acknowledge this reality before circumstances force his hand. 

British foreign policy under Starmer needs to establish both a precise direction and practical approach to understand the evolving nature of transatlantic relationships.

Imran Khalid is a physician and has a master’s degree in international relations.