In the Second World War, there was indeed a strong moral imperative, which still resonates among most people in this country and which maintains the reputation of World War II as “the good war.” There was a need to defeat the monstrosity of fascism. It was that belief that drove me to enlist in the Air Force and fly bombing missions over Europe.

Only after the war did I begin to question the purity of the moral crusade. Dropping bombs from five miles high, I had seen no human beings, heard no screams, seen no children dismembered. But now I had to think about Hiroshima and Nagasaki, and the firebombings of Tokyo and Dresden, the deaths of 600,000 civilians in Japan, and a similar number in Germany.

I came to a conclusion about the psychology of myself and other warriors: Once we decided, at the start, that our side was the good side and the other side was evil, once we had made that simple and simplistic calculation, we did not have to think anymore. Then we could commit unspeakable crimes and it was all right.