WHEN THE cold war ended, the West celebrated the peace dividend. Armies shrank, tanks were mothballed and money for defence dried up. American military spending fell from 5.3% of GDP in 1990 to 2.9% a decade later. But in Europe demobilisation went even further. Spending in western Europe slumped from an average of 2.4% to 1.6% of GDP, according to the Stockholm International Peace Research Institute (SIPRI), a think-tank, and continued to slide even after al-Qaeda’s attacks on America on September 11th 2001. A new report by the International Institute for Strategic Studies, another think-tank, shows the dramatic effect that had on Europe’s military might.

In 1990 West Germany alone was able to field 215 combat battalions (a battalion typically has a few hundred soldiers, and slots into a larger brigade). By 2015, even with Germany reunited, that had fallen to 34, a remarkable 84% cut. The number of Italian battalions fell by 67% and British ones by almost half. “To a significant degree Europeans remain dependent on US military capabilities for their defence,” concludes IISS. But American troops, who defended Europe’s frontier with the Warsaw Pact in huge numbers during the cold war, went home in droves afterwards. American forces in Europe shrank from 99 battalions to a paltry 14—from half a million troops to 76,000 today (which is still more than all but seven European NATO allies).

Critics respond that such bayonet-counting is no longer relevant to modern warfare; what matters is technology, not troops. Precision weapons (as opposed to “dumb” or unguided ones) made up 6% of all munitions used in the 1991 Gulf War. That rose to 26% in the Kosovo war of 1999, 68% in America’s invasion of Iraq in 2003 and 100% during the Libya war in 2011, according to figures collated by IISS. Far fewer squadrons could do the same job. Consider that during the second world war it took 1,000 or so bomber sorties to destroy one target. By the time of the Vietnam war, it took only 20 sorties using early laser-guided munitions. By 1991 a single warplane could hit two targets with a single pair of bombs. And in Kosovo a lone B-2 bomber could take out 16 targets in a single sortie.

But numbers still matter in some circumstances, says James Hackett of IISS. Urban warfare might require large numbers of boots on the ground, for instance. And with tiny forces, small losses can have major effects. When Norway crashed and sank a warship in 2018, its frigate fleet shrank by a fifth. Some American officials note, only half-jokingly, that Britain’s army could be lost in an afternoon of combat against a serious adversary. Perhaps most important, Mr Hackett points out that Russia has modernised its own forces—replacing 1970s-vintage Tochka-U missile brigades with cutting-edge Iskander ones—without shrinking to the same extent as western European armies.

Europeans are waking up to some of this. Last year defence spending among EU members almost returned to pre-financial crisis levels, though that represented just 1.4% of GDP on average, far below NATO’s target of 2%. European NATO members, along with Canada, will have added $130bn to their aggregate defence budgets since 2016. Germany, which accounted for a fifth of that rise, is due to activate an additional sixth tank battalion in April. That is a start, but it will be a long way back to decent levels of readiness. During a Bundeswehr exercise in 2014, hard-up commanders were forced to strap broomsticks to their armoured vehicles to substitute for machine guns.