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While you hold that Japan was not going to give up, I found that more than 60 of Japan's cities had been destroyed by conventional bombing, the home islands were being blockaded by the American Navy, and the Soviet Union entered the war by attacking Japanese troops in Manchuria. Now, when you say that they would not give up, America refused to modify its "unconditional surrender" demand to allow the Japanese to keep their emperor which needlessly prolonged Japan's resistance.
This is something I've thought on my own, but haven't heard elsewhere: "...the U.S. did not give enough time for word to filter out of Hiroshima's devastation before bombing Nagasaki". Mind you, this was three days after, the first bombing was August 6th '45, the second was August 9th '45. We are talking 1945 in the Empire of Japan... They were in a war under a dictator who proclaimed "Total war", do you think everyone went home at night to the radio's that they couldn't afford to hear someone high say "Oh, well the American's just exploded an entire city in like, maybe 30 seconds.... BUT WHO GIVES A FUCK, KEEP FIGHTING!!! BECAUSE WE ARE BLOOD THIRSTY!!!!"? No, it probably didn't happen anything like that. I mean, it's a whole city, gone. Do you think you would know if a whole city went missing? You would hear that someone who claims to be a survivor, saw Hiroshima explode and it doesn't exist anymore... and then you send some people out to check it out, and then they think "Ah, shit... what are we going to tell everyone? America just handed us our ass...", then Day three comes along and we drop our ~20 Kiloton nuke.
Furthermore: "The two cities were of limited military value. Civilians outnumbered troops in Hiroshima five or six to one". Something else I've heard before. Why wouldn't we use these devices strictly on military installations? I mean, if Japan is in the Pacific and is doing it's whole "island hopping" thing, why not just hit one island after another with these bomb...