EU enlargement alone won’t bring peace or security to Ukraine. Without matching accession promises with increased military support, writes Bjarn Eck, Europe risks prolonging the war — and exposing itself to greater danger
In just two weeks in July 2025, the US made two full U-turns on military support for Ukraine. These twists reflect the Trump administration’s erratic commitment to Ukraine — from spreading Russian disinformation and openly clashing with Volodymyr Zelenskyy, to failed attempts for a peace deal and potentially increased sanctions on Russia. Meanwhile, Russia has stepped up its airstrikes on Ukrainian cities in recent months, inflicting ever higher civilian casualties.
Europe needs a strategy that makes victory possible by matching accession promises with the resources Ukraine needs to win
What should now be clear to European leaders is that Ukraine’s future cannot hinge on Washington’s daily whims. More than three years in, Europe still lacks a clear plan to end the war — and too often assumes enlargement alone will deliver security. As others in this series argue, EU enlargement is a strategic necessity. However, it is not enough without credible, sustained military support. Europe needs a strategy that makes victory possible by matching accession promises with the resources Ukraine needs to win. Otherwise, the war drags on and Europe’s own security erodes.
From the outset, European military aid to Ukraine has been too little, too late. This is symbolised by the long list of weapons systems that were initially withheld but eventually delivered anyway – ATACMS long-range missiles, Leopard 2 tanks, F-16 fighter jets, and Patriot missile defence systems. Ukraine was also initially restricted to using these weapons solely within its own territory, a limitation lifted only recently. Afraid to escalate the war, European leaders have wasted precious time for Ukraine on the battlefield.
Yet even now, with most restrictions eased, many European countries continue to provide only minimal military support. The largest economies — Germany and the UK — have each pledged less than 0.2% of GDP annually. France, Italy, and Spain commit even less than 0.1%. In contrast, smaller states like the Baltics, Denmark, Finland, Sweden, and Poland contribute far more relative to their size. Historically, these figures are strikingly low too: Europe devoted much larger shares of GDP to far less direct conflicts. Moreover, joint EU commitments to Kyiv remain only a fraction of what was mobilised for other crises, such as the Eurozone bailouts or pandemic recovery.
Joint EU commitments to Kyiv remain only a fraction of what was mobilised for other crises, such as the Eurozone bailouts or pandemic recovery
This gap between ambition and action leaves enlargement exposed. Europe’s promise of membership is powerful, but it rings hollow if Ukraine cannot prevail on the battlefield. Limited support only prolongs the war, offering no credible path to peace. If Europe has a strategy at all, it is muddling through: letting Ukraine fight just enough not to lose — but never giving it what it needs to win.
This ‘strategy’ carries a real risk of leading to a Russian victory — for two reasons. First, a long war plays to Moscow’s strengths. Russia can draw on larger reserves of manpower and weapons, and the longer the conflict drags on, the more Ukraine’s position weakens if European support stays half-hearted. Concerns about whether Europe can sustain military aid for years to come ignore the obvious: under-resourcing Ukraine now is precisely what creates the need for endless support later. Arguments that stockpiles must be saved for hypothetical future conflicts miss the point entirely. The conflict is already here, and Ukraine is already fighting it on Europe’s behalf.
Second, a drawn-out war risks eroding public support at home. Since the full-scale invasion began, Europeans have shown remarkable unity in backing Ukraine — including its EU accession path and its military defence. In my recent research with Elie Michel for the Journal of European Public Policy, we show that many Europeans would even support increases in their country’s military aid. But public support depends on the belief that Ukraine can actually win. If leaders offer enlargement promises without the resources to make victory possible, the war will stagnate — and the sense of purpose will fade. This creates fertile ground for political entrepreneurs to exploit war fatigue and turn Ukraine’s cause into a wedge issue at home.
The consequences of a Russian victory for Europe cannot be overstated. It would embolden Moscow to push further against Europe’s eastern borders and increase the risk of direct confrontation in the near future. It would also reinforce the Kremlin’s belief that military aggression pays off, encouraging further attempts to undermine European security and democratic institutions.
A Russian victory would reinforce the Kremlin’s belief that military aggression pays off, encouraging further attempts to undermine European security and democratic institutions
The economic fallout would be severe as well. A Russian win would likely trigger a surge of Ukrainian refugees into the EU, with all the resulting domestic political pressures and polarisation. Defence spending would still have to rise, but under far more dangerous circumstances. More broadly, a Russian victory would signal to autocratic regimes worldwide that democracies fail to defend the liberal order when tested.
To prevent a Russian victory, Europe must finally commit to a clear Ukraine strategy — one focused on enabling victory. That means dramatically increasing military support, so Ukraine is no longer fighting with one hand tied behind its back. Continued US commitment should be treated as a bonus, not the backbone of Europe’s strategy.
Europe has the means, and not only from existing stockpiles. The ReArm Europe Plan unlocks extra loans and relaxes deficit rules for defence spending. NATO’s new pledge to raise defence budgets to 5% of GDP can include support for Ukraine. This must go hand in hand with maximising economic pressure on Russia, starting with confiscating frozen Russian assets.
Importantly, the cost of supporting Ukraine now is far lower than the price of a Russian victory later. Unlike Europeans, Ukrainians have already faced down Russian aggression — and proved their resolve militarily, mentally, and strategically. What remains is for European leaders to match that courage with resources and honesty. Along the way, they must clearly explain to their citizens why increased military aid, alongside enlargement, is essential for Europe’s security and democracy.