Cheap Attack, Expensive Defence: NATO 5% Pledge Following Iran and Ukraine

Two wars are teaching the same lesson. Western defence budgets and procurement priorities leave serious capability gaps when they are confronted with the asymmetry of today's conflicts. In Ukraine, Russia – with a far larger pre-war army and a 2026 defence budget four times Ukraine's – has failed to achieve its objectives for more than four years. In the 2026 Iran war, the US and Israel established air superiority within days, yet could not eliminate Iran's retaliatory capability, reopen the Strait of Hormuz, or force the political outcomes they sought. In both cases, a superpower's overwhelming advantage in troops and platforms failed to deliver decisive results. The weaker party imposed disproportionate costs on the stronger side's munitions stocks, its economy and – in the case of the US – its political will.

The two wars carry opposite signs: in Ukraine, a young democracy attacked by an authoritarian superpower fielding a post-Soviet military; in Iran, an authoritarian regime struck by a superpower fielding the most advanced forces in the world. Yet for Europe's budget planners and procurement officials, they yield one coherent set of lessons.

Neither Iran nor Ukraine found a way to defeat a superpower's forces decisively on the battlefield. Both found ways to make a superpower's victory expensive – and potentially unaffordable – by shifting the contest into domains where the Western alliance has under-invested: the economics of munitions, the protection of infrastructure far behind the front line, commercial risk, and the public's confidence in everyday security. The vulnerability at the heart of Europe is rooted in two decades of procurement choices: exquisite platforms bought in small numbers, acquisition concentrated in a few large and often slow-moving prime contractors, a deficit of innovation and chronic neglect of precisely those civilian systems and infrastructure that adversaries now treat as the primary battlespace.

The Mathematics of (Air) Defence

The arithmetic is simple: defending often costs a hundred times more than attacking. Over the 39 days of the campaign against Iran, Gulf and US air defences expended hundreds of Patriot interceptors, at roughly $4 million each, against Iranian Shahed drones costing, at the top end, tens of thousands of dollars. Iran launched an estimated 4,000 one-way attack drones; by day four it had fired more than 500 ballistic missiles and 2,000 drones. Interception rates exceeded 90% – a genuine proof point for US-made systems. Even so, by the Center for Strategic and International Studies' estimate, the US expended roughly half its Patriot inventory, more than 850 Tomahawk cruise missiles and over 1,000 air-launched stand-off weapons. Rebuilding those stockpiles will take four to five years.

This is the asymmetry in its purest form. When every incoming weapon costs the attacker a fraction of what its interception costs the defender, the defender can win every engagement and still lose the war of stockpiles, available funding and public patience.

Ukraine is running the same play in reverse against Russia. Cheap, domestically produced drones have fought a much larger force to a frozen front line and carried the war deep into Russia – against refineries, airfields, ships and military logistics nodes. With uncrewed surface vessels costing a few hundred thousand dollars each – less than a single modern torpedo – Ukraine has knocked out around a third of Russia's Black Sea Fleet and immobilised the remainder, without operating a conventional navy of its own.

The lesson is not that high-end interceptors are useless. It is that air defence must be cheap to produce and deep in its layering. The Alliance needs large stocks of low-cost counter-drone effectors – short-range air defences, directed-energy weapons, interceptor drones, guided rockets – and should reserve its scarce high-end systems for the ballistic and cruise-missile threats that genuinely require them.

Targeting Society, Not Soldiers

The second lesson: autocratic regimes do not primarily aim at Western forces. They aim at the political and economic system of open societies. Iran never achieved sea control in the Strait of Hormuz; it did not need to. Within days, crude oil exports fell by 95% and liquefied natural gas by 99% – the largest supply disruption in the history of the oil market, in the International Energy Agency's judgement. Iran achieved this with technologically unsophisticated means: sea mines, short-range missiles, swarming fast boats and, above all, enough demonstrated resolve to convince insurers, shipowners and energy markets that transit was not worth the risk. Clearing the mines, the Pentagon told Congress, could take six months – and only once the war had ended.

Russia applies the same logic below the threshold of open war. Its campaign against Europe runs on arson, sabotage, GPS jamming that disrupts civil aviation over the Baltic and Scandinavia, and repeated damage to undersea power and communications cables by shadow-fleet vessels sailing under third-country flags. Analysts have documented some 150 suspected hybrid incidents across NATO and the EU since early 2022. The aim of this campaign is not destruction at scale; it is to impose costs, sow doubt and persuade European voters that supporting Ukraine carries the risk of escalation – while remaining deniable enough to avoid a resolute NATO response. As long as such operations cost little and generate disproportionate political anxiety, they will continue.

Making the 5% Count

In a war of attrition, mere survival is sold to the public as victory. Self-confident nations that understand these asymmetries can deny victory to far stronger opponents. But treating asymmetric capabilities as a silver bullet would be a strategic error for the Alliance. Ukraine's naval-drone successes came substantially against ageing Soviet-era hulls never designed to counter low-signature threats; different results should be expected against modern, layered defences. And Russia, unlike Iran, retains a substantial air force and sophisticated integrated air defences. A wider Russia-NATO confrontation would therefore likely resemble a more intense version of the Middle East war – large salvos saturating and eventually overwhelming defences not built for depth – and it would be preceded by sabotage and targeted disruption of critical civilian infrastructure. That is precisely why the correct inference is not to swap one force structure for the other. NATO must field both: the conventional deterrent core and the asymmetric layer, including the ability to impose asymmetries of its own on an attacker.

The commitment to spend 5% of GDP on defence is historic, and as NATO leaders meet in Ankara this week to turn the Hague pledge into delivery plans, the real question is what the money will buy. The danger is that taxpayers' money flows overwhelmingly into familiar platforms and programmes rather than the innovative solutions needed to avert – or win – an asymmetric exchange.

A concrete, fundable agenda follows. Invert the cost curve of air defence with cheap, layered, mass-produced counter-drone systems. Build offensive, long-range strike capacity at low unit cost, to hold an adversary's launchers and defence-industrial nodes at risk – Ukraine is doing exactly that, with success. Recapitalise neglected mine countermeasures and the protection of undersea infrastructure, including the unglamorous capacity to repair severed cables. Fund resilience: hardened, redundant nodes in energy, transport and telecommunications, and navigation that survives jamming. Fortunately, NATO has earmarked 1.5% of GDP precisely for this civilian resilience and innovation. The challenge now is to reform procurement and decision-making so that more of these capabilities reach the force by the time Donald Trump’s time in office comes to an end.

There are grounds for cautious optimism. The asymmetric advantage NATO's adversaries hold today is reversible – if the West directs attention and money to the domains where asymmetric wars are fought. The US still leads the world in capital formation, innovation, entrepreneurship and its defence-industrial base. The UK leads Europe in AI. Germany retains world-class research in the technical disciplines and – still – a strong industrial base. The adversaries simply made a strategic decision to build capabilities in, and take the fight to, the domains the Alliance did not prioritise. The 5% pledge supplies the means. Whether that money buys civilian resilience and asymmetric advantage will decide whether Europe can hold the ambitions of autocratic regimes in check. Taxpayers and voters will only sustain the effective defence of democracy if the math adds up.

© Andreas Urbanski, 2026, published by RUSI with permission of the author.

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