At 8.15 a.m. on 6 August 1945, a B-29 bomber called Enola Gay dropped ‘Little Boy’ over Hiroshima. The thermal radiation from the atom bomb was 900 times more searing than the sun. An estimated 118,661 civilians died, horribly. Survivors staggered about with their skin in shreds, their intestines hanging out and their blacked and bleeding faces grotesquely disfigured.