Twenty-two years have passed since NATO’s 2004 Istanbul Summit. At the time, the Alliance’s agenda reflected the defining features of the post-Cold War era: globalisation, new forms of terrorism and asymmetric threats, the U.S. invasion of Iraq, and NATO’s eastward enlargement. The NATO Summit, set to convene in Ankara next week, will not only showcase how the transatlantic alliance’s priorities have evolved over the past two decades but also provide a revealing glimpse into President Donald Trump’s approach toward European allies.
Unlike previous NATO summits, which were largely organised around a single dominant security challenge, the Ankara meeting takes place amid the convergence of multiple strategic transitions. The Alliance must simultaneously adapt to a prolonged war in Ukraine, recalibrate the posture in the Middle East following the Iran conflict, mounting pressure on global connectivity corridors, and an American administration that increasingly evaluates alliances through the lens of measurable strategic returns rather than shared political values. It is this convergence—not any single crisis—that makes Ankara a particularly consequential moment for the future of the transatlantic alliance.
The summit agenda will inevitably revisit two issues that have dominated NATO discussions over the last four years: the now-protracted Russia-Ukraine war and the regional and global repercussions of the recent Iran war. While neither war has directly targeted NATO member states, both have exposed significant vulnerabilities in the European and Middle Eastern security architectures. Equally important is the growing crisis surrounding connectivity corridors that sustain the flow of goods, services, energy, and people. As illustrated by the prolonged weaponisation of the Strait of Hormuz, conflicts can disrupt critical trade routes for months, imposing collective costs that extend far beyond the battlefield.
Yet the summit will also take place amid growing anxiety for Europe amid President Trump’s second term. Last year’s communiqué committed allies to increasing defence spending to 3.5 per cent of GDP by 2035 and strengthening indigenous defence capabilities through modern industrial investment. While such demands have long been synonymous with Trump’s approach to burden-sharing, his isolation during the war against Iran has further strained relations with European partners.
European NATO members—particularly the E5 coalition of Germany, France, the United Kingdom, Italy, and Poland—are expected to maintain a hard-line position toward Russia and continue advocating robust support for Kyiv. The recent E5 meeting in Berlin reiterated calls to pressure Russia into negotiations and provide Ukraine with long-term security guarantees. However, the decision by German Chancellor Friedrich Merz and French President Emmanuel Macron to engage Ukrainian President Volodymyr Zelenskyy in an E3 format earlier this month was not particularly well received in either Rome or Warsaw, highlighting some rifts within Europe itself.
Although European allies welcomed Trump’s deal-making on Iran, their support resembled that of a privileged audience who, after watching a lengthy performance from the back rows of a theatre, offer polite applause out of courtesy rather than conviction. Trump, for his part, appears to believe he was left largely alone to manage a conflict he could not fully contain. Such perceptions are likely to reinforce his longstanding criticism that European NATO members continue to behave as free riders under the Alliance’s security umbrella.
More fundamentally, however, the debate extends beyond burden-sharing alone. The second Trump administration increasingly appears to question not only how much Europe contributes, but also the extent to which the United States should continue underwriting European security as a strategic default. In this reading, defence spending targets are less an end in themselves than a proxy for a broader redistribution of strategic responsibility within the Alliance.
The Trump administration is unlikely to be persuaded by idealistic calls for a more “Europeanised” NATO unless those aspirations are accompanied by tangible commitments. For a White House guided by transactional foreign policy, actions matter far more than rhetoric. If European governments fail to demonstrate measurable progress toward the 3.5 per cent defence spending target by 2035, scepticism in Washington will only deepen. Moreover, if Chancellor Merz’s criticism of the Iran conflict as ill-conceived is followed by rapid American decisions—such as directives to withdraw 5,000 U.S. troops from Germany—then the Ankara Summit could become a high-stakes exercise in self-validation for Europe. Failing that, European allies may face concrete consequences, including reductions in the American military presence and cuts to NATO’s collective defence budget commitments.
European NATO members, therefore, find themselves trapped in a difficult geopolitical dilemma. While seeking to lead diplomatic efforts toward a ceasefire in Ukraine, they are simultaneously being compelled to assume greater responsibility for the continent’s long-term security architecture. Having realised that past defence investments have failed to satisfy Trump’s expectations on burden-sharing, European capitals are scrambling to adapt. Through initiatives such as the Prioritised Ukraine Requirements List (PURL), European governments are aggressively funding military procurements and defence assistance for Kyiv while laying the groundwork for future security guarantees that would bind Europe to Ukraine’s post-war stability. By taking a more active role at the negotiating table and pledging to enforce any eventual peace settlement, Europe is attempting to demonstrate strategic self-sufficiency and convince a transactional American administration that it can manage the war on its doorstep without constant U.S. intervention.
Yet beyond defence spending and Ukraine, NATO’s European pillar faces a deeper challenge: an identity crisis. Most European allies, almost all of them members of the European Union, remain prone to viewing transatlantic affairs through a Brussels-centric lens in diplomacy and strategic vision. European Commission President Ursula von der Leyen’s April gaffe that “We must succeed in completing the European continent so that it does not fall under Russian, Turkish, or Chinese influence” reflects this mindset. Such a worldview reinforces a pernicious “us versus them” dichotomy that often prevents European allies from fully appreciating Ankara’s strategic significance on NATO’s southern flank. It also causes them to miss substantial opportunities for cooperation in the defence industry.
Italy, fortunately, has adopted a more pragmatic approach. The acquisition of Piaggio Aerospace and the expansion of cooperation with Leonardo by BAYKAR, one of the world’s largest drone exporters, demonstrate a strategic realism that stands in stark contrast to many Brussels-driven prejudices associated with Türkiye’s EU membership process. The same European-centred thinking can arguably be seen in the fate of the 2022 Istanbul talks, where a potential ceasefire between Russia and Ukraine appeared within reach before being undermined by the intervention of then-British Prime Minister Boris Johnson. Four years later, European actors have yet to produce a viable solution through their own mechanisms.
More broadly, the Ankara Summit reflects a wider transformation in transatlantic relations. For much of the post-Cold War period, NATO operated on the assumption that American strategic leadership constituted a stable foundation of European security. That assumption is now being tested. The challenge facing European allies is therefore not simply to spend more on defence, but to redefine their role within an alliance whose internal distribution of responsibilities is becoming increasingly contested.
Ultimately, the upcoming NATO Summit may serve as a crucial barometer for the widening rift between Trump and Europe’s allies. The positions taken on the Russia-Ukraine war, the Iran conflict, and defence spending commitments will reveal whether this divide remains manageable—or whether it is destined to grow even deeper. The answers emerging from Ankara may well shape the future of the transatlantic alliance for years to come.
