THE HAGUE, Netherlands – Former U.S. President Donald Trump arrived in The Hague this week for his sole full day at the NATO summit, stepping into an alliance that has, in many ways, bent to his long-standing will. His presence has reignited a familiar blend of deference and deep apprehension among member states, who grapple with his past threats to withdraw U.S. support and his persistent demands for increased defense spending.

The summit, hosted in the Netherlands, provides a crucial stage for Trump to assess the progress made on his key demands while simultaneously casting fresh doubt on the foundational principle of collective defense. Even before his arrival, Trump underscored his transactional view of the alliance, raising questions about whether the United States would come to the aid of member states that fail to meet defense spending targets. This stance, though controversial, has undeniably spurred a significant shift in European defense policy.

The Alliance Under Pressure: Trump's Enduring Influence

For years, Donald Trump has been a vocal critic of NATO, accusing European allies of freeriding on U.S. military might. His consistent rhetoric, often delivered via public statements and social media, pushed the alliance’s 2% of GDP defense spending target to the forefront of international discourse. This pressure has yielded tangible results: many NATO members have significantly increased their defense budgets since his initial presidency. According to NATO figures, a growing number of allies are now meeting or are on track to meet the 2% threshold, a direct consequence of the persistent U.S. demand.

However, this increased financial commitment comes at a cost of heightened anxiety. European leaders, particularly those in Eastern Europe, remain acutely concerned about the reliability of the U.S. commitment to Article 5 of the NATO treaty, which stipulates that an attack on one member is an attack on all. Trump’s past suggestions that he might not defend allies who fall short of spending targets have sowed seeds of doubt that continue to undermine the very principle of mutual defense, a cornerstone of NATO’s existence since its inception in 1949.

European Response and Lingering Doubts

Despite the pressure, European NATO members have largely responded by boosting their military capabilities. Nations like Poland, Germany, and the Baltic states have accelerated their defense investments, acquiring new equipment, modernizing forces, and participating more actively in joint exercises. This strategic reorientation is driven not just by U.S. demands but also by a heightened awareness of regional security threats, particularly in the wake of renewed geopolitical tensions.

Yet, the fundamental question of U.S. commitment persists. Many European diplomats and defense officials privately express concern that even if spending targets are met, a future U.S. administration might still question the value of the alliance, potentially eroding the unity and deterrent effect NATO provides. This underlying tension shapes the atmosphere of the current summit, where leaders seek both reassurances from the U.S. and a clear path forward for an alliance navigating an increasingly complex global landscape.

The Path Forward for NATO

The summit in The Hague serves as a critical juncture for NATO. While the alliance has demonstrably adapted to some of Trump's demands, the core challenge remains balancing the need for burden-sharing with the imperative of unwavering collective security. Discussions are expected to focus not only on defense spending metrics but also on strategies for strengthening deterrence, enhancing readiness, and addressing emerging threats, including cyber warfare and hybrid operations.

For NATO, the task is to solidify its internal cohesion and present a united front, demonstrating its continued relevance in a volatile world. The immediate future of the alliance hinges on its ability to reconcile the varying expectations of its members, particularly those concerning the unwavering application of its foundational principles in the face of political shifts.