I fully support questioning the wisdom of that move, but the fact remains that the government that dropped the bomb(s) was not the aggressor in that conflict... in a world war where the stakes were ridiculously high. I think thats an extremely important bit to contextualize that event, when compared with say... Nazis, Hitler, and Auschwitz.
> in a world war where the stakes were ridiculously high
The context of a World War - even more so than that of any other war - makes it much easier for any government to do what it likes. Which most often means to kill lots and lots of people.
What I argue is that such context is very different from a time of peace. It's not really fair to include WW2 atrocities when talking about the number of deaths caused by guns in a peace-time.
The GP tried to do exactly that, which I disagree with in itself, and moreover forgot to include any other "government [that] murdered millions of unarmed civilians" in their argument. I don't have a strong opinion on whether Hiroshima and Nagasaki were a good or bad idea, I just pointed out that, in that single operation, the US government effectively "murdered hundreds of thousands of civilians". Again, that's nothing surprising, nuclear weapons are designed to do just that.
So, again, it was war. People die in wars. That's what the wars are for, basically. Now, since then, we're at peace (here in Europe, at least). The number (and rate) of deaths caused by guns during this peaceful time is overwhelmingly higher in the US than in Germany. That's it, I don't mean anything else, just that this is a fact and that mentioning Auschwitz is not a valid counter-argument for this.
You might want to reconsider these assumptions. There's a lot of history and economics to cover, but I don't believe it is fair to say it was so clear-cut who the aggressor was. When the US had economically ravaged China and then sent Perry to open trade; the Japanese had refused, so Perry went and fired a shell in Tokyo (Edo, then) Harbor. The Japanese then went through trials of trying to play along: one Japanese diplomat put it, 'When the West won the game of poker at the world's table, they then as the victors declared the game immoral,' which describes Japans geopolitical situation. There was economic warfare against Japan, first.
Germany also had economic warfare waged against them and this should not even be controversial--even mainstream "modern-day priests" like the hugely influential economist Keynes had said this.
That said the Japanese empire was an evil one, like most empires, but when the bombs were dropped on civilians the war was already over--that is why Eisenhower said "there was no reason to use those things."