The artillery shells ran out faster than anyone had planned for. That, more than any summit communiqué or think-tank report, is the lesson European defence planners took from Ukraine. When Russia launched its full-scale invasion in February 2022, it exposed not merely a diplomatic failure but a continental one: decades of shrinking budgets, hollowed-out arsenals and a quiet, collective bet that serious war on European soil was a thing of the past. Three years on, Europe is paying — literally — to reverse that assumption. The question is whether the cheque is large enough, and whether it will clear in time.
The Long Hangover of the Peace Dividend
NATO was born in April 1949 from the rubble and anxiety of the post-war world. For its first four decades it was taken with deadly seriousness, absorbing substantial shares of Western national income and generating the doctrine, hardware and manpower to face down the Soviet Union. Then the Wall fell. The peace dividend that followed was, in retrospect, a prolonged act of strategic wishful thinking.
Between 1990 and 2014, average defence spending among European NATO members fell from roughly 3 per cent of GDP to barely 1.4 per cent. Armies shrank. Tank fleets were sold off or mothballed. Ammunition stockpiles were run down to levels that assumed only short, low-intensity interventions. The 2014 Wales Summit, prompted by Russia's annexation of Crimea, set the now-famous 2 per cent of GDP target. At the time, only three or four European allies met it. Most treated it as aspirational — a political commitment they could defer almost indefinitely.
Ukraine ended that deferral. By 2025, according to NATO's own figures, 23 of 32 alliance members are meeting or exceeding the 2 per cent threshold, compared with just three in 2014. Total European NATO defence expenditure has risen by more than 20 per cent in real terms since 2022. Poland, sharing a border with both Russia and Belarus, is now spending close to 4 per cent of GDP on defence — the highest proportion of any ally. The Baltic states, for decades ignored in alliance planning, have become some of its most vocal and credible voices on deterrence.
What the Money Is Actually Buying
Spending figures, however impressive, can obscure as much as they reveal. The harder question is what this money is producing — and how quickly.
The most urgent priority has been replenishing munitions consumed or donated to Ukraine. European factories that had spent years producing shells in the hundreds of thousands are now being retooled and expanded to produce in the millions. The European Commission's Act in Support of Ammunition Production, launched in 2023, was a first step. Progress has been real but slower than promised. Defence industries that were deliberately kept lean during the post-Cold War years cannot be scaled up overnight. Supply chains for propellants, explosives and metals are straining under simultaneous demands from multiple governments.
Beyond ammunition, European governments are making substantial investments in air defence — a category grotesquely underweighted before 2022. Germany's purchase of the Patriot system, Poland's expanding network of short- and medium-range interceptors, and the broader push to acquire or develop next-generation layered air defence reflect a hard lesson from the skies over Kyiv and Kharkiv. Drones, long treated as a niche capability, are now a central procurement priority across the continent.
The UK, for its part, committed in 2025 to raising defence spending to 2.5 per cent of GDP, with a longer-term aspiration towards 3 per cent. The announcement was welcomed by allies, though defence analysts were quick to note that the Ministry of Defence has a well-documented record of ambitious commitments and troubled procurement. The Ajax armoured vehicle programme — years late and billions over budget — remains a cautionary emblem of what can go wrong when ambition outstrips institutional capacity.
The Political Economy of Rearmament
Spending more on defence sounds simple. It is not. Every pound, euro or zloty directed at a new frigate or a howitzer battery is a pound, euro or zloty not spent on hospitals, schools or pension systems. In an era of constrained public finances and sceptical electorates, selling rearmament is politically demanding work.
The arguments being deployed across European capitals share a common structure: investment now prevents far greater costs later. Defence, on this reading, is an insurance premium. That framing has gained traction since 2022, but it faces persistent counter-pressure. In Germany, constitutional debt limits complicated efforts to finance the much-heralded €100 billion special defence fund; creative accounting was eventually required. In France, the defence budget has grown but remains below the level President Macron's own planning laws envisaged. In Italy, political instability has made sustained commitment difficult to maintain.
There is also the question of what European "strategic autonomy" — a phrase Macron has championed for years — actually means in practice. Does it mean the ability to act independently of the United States if necessary, or merely a more equitable burden-sharing within a US-led alliance? The two visions imply different industrial strategies, different command arrangements and different diplomatic relationships with Washington. The debate is real, and it is unresolved.
NATO's Test: Credibility and Cohesion
At the Washington Summit in July 2024, marking the alliance's 75th anniversary, leaders approved a new regional defence plans architecture and reaffirmed that NATO's collective defence guarantee remains "ironclad." The language was robust. The optics were carefully managed. But beneath the communiqué, the alliance faces structural tests that money alone cannot resolve.
The most significant is coherence. NATO now has 32 members, ranging from the United States — still by far the largest defence spender — to small nations whose militaries number in the thousands. Coordinating acquisition, logistics, doctrine and command across that diversity is a formidable challenge. The alliance's new force model, which aims to keep 300,000 troops at high readiness, is ambitious; whether the member states will actually generate those forces on the timelines promised is an open question.
The transatlantic relationship, meanwhile, remains the alliance's indispensable load-bearing wall — and its most politically uncertain element. American commitment to European defence has fluctuated with administrations and will continue to do so. The lesson European defence planners have drawn is clear: they cannot afford to plan on the assumption that US support at current levels is guaranteed indefinitely.
None of this negates the significance of what has changed. In 2019, a serious conversation about European rearmament would have been confined to a small circle of hawkish analysts and nervous Baltic politicians. Today it occupies the front pages, the budget committees and the factory floors of a continent that has rediscovered, at considerable cost, that security is not a given. NATO at 75 is neither the complacent institution of the 2010s nor the lean, battle-hardened alliance of the Cold War. It is something in between: awakened, investing heavily, but still working out, in real time, whether the changes it is making will prove sufficient for the world it now inhabits.