Santa (and anyone with common sense) -- look at the barbarism of Japan, the slaughter of the Jews by the Nazis, the 12 million killed by our "ally" and soon-to-be-enemy Russia...Sitting in our comfortable, exessivley large house, or our well equipped dorm rooms, never worrying about where our next meal will come from, trying to figure out how we will amuse ourselves today with our pile of technology...we have no concept of life in the 1904's, let alone life in the early 1900's in general. The people "on top" waging World War two had lived through a *horrific* war in World War I, where we saw mustard gas killing people from the inside out, and then the escalation of weapons through the course of World War II, up to and including the use of the atomic bomb.
For *anyone* to sit around an say "Well, I read some (biased) paper by some historian, and I have conluded there was no rational cause to use the atomic bomb" is simply ignorance. There were a hell of a lot of good reasons to use the atomic bomb, but the *primary* reason was to say, "Hey, we are the biggest baddest motherf*ers on the block now, we've got this, and you bad better back the f* down...
I will remind you all that *after* this "evil" attrocious act of dropping the a-bomb, we proceeded to essentilaly rebuild out enemies countries, pouring more of our national treasury in to the people that had years prior intended on conquering and subjugating the world.
You simply can NOT take this one event in some narrow context and try to judge it. The use of the atomic bomb is arguably the culmination of global war that started in World War I.
The fact remains that nobody has used one since then, and that while it can be argued that war has continued essentially without ceasing since world war II (i.e. there is *always* a war somewhere, and yes, a great many of them are US proxy wars), there has never been conflict or death and destruction that even approximates the global mayhem that was World War II.
It was a damned good decision when examined in the *full* context of global politics and conflict over the last, say, 112 years.