Russian roulette: what ‘tactical’ nuclear war would mean

In 1861 an American seed-drill designer named Richard Jordan Gatling created a super-weapon that he believed would bring an end to war. With his hand-cranked, ten-barrel machine-gun, Gatling did for warfare what his contemporary Isaac Singer had done for sewing, bringing mechanisation to a former handcraft. Gatling’s gun fired more than 200 rounds a minute – as much as an entire battalion of soldiers with muzzle-loading muskets. In his memoirs, Gatling wrote that ‘if a four-man machine-gun crew could kill a thousand infantrymen in five minutes’ then perhaps the terror created by such a weapon would ‘discourage war altogether’.

Robert Oppenheimer, the creator of the first atom bomb, was motivated by a similar thought. ‘The atomic bomb has made the prospect of future war unendurable,’ wrote Oppenheimer. ‘It has led us up those last few steps to the mountain pass and beyond there is a different country.’