The Surrender of Japan was not entirely the result of the two atomic bombs. We had hit some 60 Japanese cities with our regular H.E. [high explosive] and incendiary bombs and, as a result of our raids, about 241,000 people had been killed, 313,000 wounded, and about 2,333,000 homes destroyed. Our B-29s had destroyed most of the Japanese industries and, with the laying of mines, which prevented the arrival of incoming cargoes of critical items, had made it impossible for Japan to carry on a large-scale war…Accordingly, it always appeared to us that, atomic bomb or no atomic bomb, the Japanese were already on the verge of collapse.
Memoirs of General H.H. Arnold, Commander of the American Air Force in the Second World War (1949):