Oh yeah, one more thing about the atomic bomb that I never understood, and which I definitely don't remember learning in 7th grade history:
The bomb was for the Russians.
Right, the Japanese were just about defeated and trying to work out surrender talks. But we needed to show the Russians that we had the bomb, and blowing up a deserted island (say) in front of world representatives wouldn't cut it. We had to off some people, preferably non-white. I suspect the non-whiteness made it not only easier, but possible. The Japanese were already "faceless."