In the build-up to D-Day in 1944, American GIs in Britain withstood jokes that they were “oversexed, overpaid, and over here”. This may have reflected, among other things, the greater wealth – and resources – of Britain’s newly senior military partner. The Economist ran an article earlier this year on the British Army overseas, entitled “overstretched, overwhelmed and over there”. The joke is now on the Brits, but still refers to the growing perception of an under-resourced British force being asked to perform beyond its means, once again alongside a far better-equipped American one. The issue has recently come to ahead around helicopters, of which Britain allegedly has under 30 in Afghanistan, while the US has over 120 (4 times as many). Although this is broadly in proportion to troop numbers (8,000 Brits vs 28,000 GIs, or 3.5 times as many), many of the British choppers are non-troop-carrying. The media contends that rising British casualty levels could be mitigated if the troops were able to travel by air like their American colleagues, rather than over land as they currently tend to. Clearly helicopters are expensive (the latest consignment of Merlins cost the MoD £35 million each), so how much do we spend on our armed forces compared to our allies? In absolute terms, America outspends Britain by a factor of 10 ($636 billion versus $65 billion). But then it’s a far bigger and richer nation; Britain still has the world’s fourth-highest defence budget (after the US, China and France). So we have decided to focus our analysis on relative measures. The chart below shows how much each of the major ISAF partners spends per member of its armed forces. Australia and the US both spend roughly 50% more per soldier than Britain, which should result in better-equipped troops. Note that while Australia has a far smaller army than the UK (51,000, which equates to around ¼ of Britain’s), it spends significantly more per soldier. It is also instructive to compare defence spending as a percentage of GDP, as in the chart below. Once again, Britain comes third, this time after France, which spends 2.6% of GDP, vs 2.4% for Britain. America spends over 4%. In relative terms then, Britain does outspend most of its ISAF allies on defence (only America spends significantly more on both measures). Ultimately, this could suggest a need for British governments either to fundamentally re-appraise the priority which they attribute to their military role abroad, or to re-align spending with expectations and requirements. We won’t be the first to have suggested this. Relative to troop numbers and national wealth, to match America Britain would need to up its annual defence budget by over half, or around $35 billion (around £21 billion). For a bit of context, the proposed upgrade of the nuclear deterrent would cost £25 billion.