During the Peloponnesian War in 416 BCE, Athens sought to force the small island of Melos into submission. Despite its historical ties to Sparta, Melos remained neutral and refused Athenian demands to join their empire. In response, Athens issued an ultimatum: surrender, pay tribute, or face annihilation.
Thucydides recorded this dramatic exchange, known as the Melian Dialogue. Speaking from a position of power, the Athenians dismissed the Melians’ appeals to justice and Spartan aid. They bluntly asserted that “the strong do what they can, and the weak suffer what they must.” The Melians refused to yield, believing their allies would come to their rescue. But Athens, acting ruthlessly, sacked Melos, executed its men, enslaved its women and children, and repopulated the island with Athenian settlers.
The destruction of Melos exemplified Athens’ callous realpolitik, prioritising strength over principles. It also eroded Athens’ moral authority, deepening opposition to its empire. Ironically, this historical episode echoes contemporary power struggles, especially the unfolding drama of transatlantic relations.
As the world prepares for a Trump-led ceasefire for the war in Ukraine, Europe is experiencing a Melian moment of their own. Trump’s first term made it abundantly clear that U.S. security commitments are not set in stone. Following a heated Oval Office exchange between President Trump, Vice President J.D. Vance, and Ukraine’s Zelenskyy, European leaders are waking up to the possibility that Washington’s strategic calculus may no longer align with their own. Now, America’s ties with Europe are more uncertain than ever.
Europe, perhaps for the first time, is thinking over strategic autonomy in defending the continent’s future. The European Commission’s Ursula von der Leyen recently unveiled the ReArm Europe initiative, proposing the mobilisation of €800 billion for defence. Meanwhile, in response to Trump’s decision to cut military aid to Ukraine, UK Prime Minister Keir Starmer convened European leaders, calling for a coalition of the willing to ensure a just resolution to the war.
Trump’s stance has undoubtedly ignited a new sense of urgency in Brussels. While strategic autonomy is an admirable goal, the harsh reality remains: A European security architecture without the U.S. is nearly impossible for many reasons.
First, the European Union is divided, making it less capable of forging a unified front for a collective defence mechanism. Take European Commission President Ursula von der Leyen’s ReArm Europe initiative—it doesn’t introduce fresh funding but instead proposes joint borrowing within the EU. Yet, this is easier said than done. France’s public debt has surpassed €3.2 trillion, Italy follows closely with €3 trillion, and Spain holds €1.62 trillion—all well above the EU’s 60% debt-to-GDP regulatory cap. Given this financial landscape, introducing another debt-financed mechanism is unlikely to be welcomed with open arms.
Even if the EU were to pursue such a burden-sharing model, it risks transforming the bloc into a debt-financed union—something Germany, which has historically shouldered the heaviest financial burden, would vehemently oppose. Evenif funding were secured, the long-term contracts required for a defence framework could easily conflict with national political interests. When it comes to defence, history has shown that EU member states tend to prioritise national interests over collective security.
Second, NATO’s European defence doesn’t exist in an EU-only vacuum—it includes major non-EU members like the UK and Türkiye, both of which possess formidable military capabilities, particularly Türkiye’s army, the second largest in NATO. Crafting an effective security framework that includes such players demands robust intergovernmental coordination. But here’s the problem: the EU is grappling with a leadership crisis that severely hampers its ability to spearhead such an initiative. With their pro-Trump stances on Ukraine, leaders like Slovak PM Robert Fico and Hungarian PM Viktor Orbán seem to sing outside the chorus, complicating discussions within the EU on security strategies.
If the EU is serious about defence autonomy, it must prioritise realpolitik over the value-laden policies that have long shaped its approach to Türkiye. The reality is clear: Türkiye has NATO’s second-largest military in Europe, but its involvement won’t come without challenges due to the EU’s politicized stance and opposition from members like Greece and Greek Cyprus. If the EU aspires to be a geopolitical power rather than a political idealist, it must give up its ideational thinking, abandon its habit of adapting foreign policy to ideological frameworks, and embrace a more pragmatic approach.
Another key point is recognising Trump’s rhetoric for what it is—his threats to leave NATO serve as leverage to gain more concessions from European countries. Last year, a bipartisan bill spearheaded by Democrat Tim Kaine and current Republican Secretary of State Marco Rubio effectively barred any U.S. president from unilaterally pulling out of NATO. However, this doesn’t mean Washington won’t attempt to undermine the alliance by other means—by reducing its military footprint in Europe, for instance. This is precisely what alarms European leaders. If the U.S. were to weaken its NATO commitment, it would dismantle the Western security order it helped build—an act with irreversible consequences.
Trump’s NATO rhetoric is, in essence, a wake-up call for Europe. It’s pushing EU leaders to take burden-sharing more seriously than ever before. If they fail to step up, the prospect of a U.S. withdrawal—or at least a severe reduction in American military presence—would leave Europe facing its own Melian moment. And Trump plays this game with unsettling realism, forcing Europe to see a U.S.-less NATO not as an opportunity for strategic autonomy, but as an outright nightmare.
In short, as the EU wrestles with internal divisions and a leadership vacuum, it also confronts the limits of its ambitions beyond being an economic bloc. If an eventual Ukraine ceasefire tilts in Moscow’s favour, Brussels will not only seek to consolidate its internal unity but also recognise just how constrained its strategic manoeuvring is. That moment—when the EU fully grasps both what it is and how much further it must go in defence spending—will be a defining one.
