I was reading about Richard Feynman, some time ago. I knew he was an American Physicist, and that he had something to do with the Manhattan Project which Einstein (who was an attendee at the first seminar of Feynmen's at Princeton University) contributed to. But I found some info which said Einstein was at one time a pacifist, but urged the United States in proceeding to develop the atom bomb before Germany did. (By the way, I realize you know all of this - but you must indulged me..!) Feynmen was encouraged by another physicist, Robert Wilson to take part in the Manhattan project, and so he and Hans Bethe developed the Bethe/Freynmen formula for calculating the yield of a fission bomb.
The first test which was code named Trinity, had Freynmen claim to be the only person to see the explosion without wearing the very dark glasses that were provided. Reasoning that it was safe to look through a truck windshield, as it would screen out the harmful ultraviolet radiation. All of this of this of course led to 'Little Boy' being detonated in Hiroshima. Such great minds brought together to develop something so devastating. But when the second bomb was released on Nagasaki, in one split second the population dropped from 422,000 to 383,000... In one split second! Yet scientists estimated that both bombs only utilized 1/10th of 1 per cent of their explosive capabilities.
Incredible. I have read that dropping those two bombs was unnecessary, as the Japanese had already been defeated and they posed no serious threat. Mind you,1994's Rwandan mass murder wiped out about 800,000 people, that is like five Hiroshima's and it only happened 17 years ago. These scientists were constructing a bomb the likes of which the world had never seen, but Freynman did had his regrets about the Manhattan project.