Today is Hiroshima Day, the anniversary of the first use of a bomb so powerful that it would come to threaten the existence of the human race. Only two such devices have ever been used, but now, a decade after the end of the cold war, the world faces new dangers of nuclear attack – from India, Pakistan, Iraq, al-Qaida, and even the US. Launching a special investigation into nuclear weapons, Paul Tibbets, the man who piloted the Enola Gay on its mission to Japan, tells Studs Terkel why he has no regrets – and why he wouldn’t hesitate to use it again.