Quote Originally Posted by nik0tine
As for the argument of could we have warned them? The U.S. built the bomb and didn't even fully comprehend the power it had until after they dropped them.
Oh bull. We didn't know the bombs power? We knew damn well that it was going to level an entire city and kill thousands of people. Don't even try to tell me that we "didn't know that"
I may be mistaken about the A-bomb, but I'm fairly sure they were uncertain how powerful the H-bomb was (not entirely related no, but I just may be confusing the two). I believe there was talk about the potential to set the atmosphere on fire with the H-bomb (someone feel free to correct me if I'm wrong here).

However my point stands that Japan wouldn't have a clue how powerful it was, and they'd have absolutely no reason to believe American estimates of its power, or that they even had it in the first place.

And as was already said, they could have surrendered after the first one and didn't. They were not prepared to give up, and had they been left alone, they would have simply rebuilt and been given time to recover from their defeat in the Pacific. Giving them time to rebuild their carriers, and train new pilots would have been a bad idea. Like it or not, those bombs ended the war, and with less loss of life on both sides than a full blown invasion would have.