“Funny no one has mentioned the firebombing of German and Japanese cities.”
I was just think that as I opened your comment. We killed millions by carpet bombing cities, not to mention a few nukes we let loose.
It was a necessity, particularly in Japan.
In the accounts by many people (one of them Louis Zamperini) who walked through the destroyed neighborhoods as a prisoner, he saw, the only upright objects poking through the ashes, industrial machinery.
War industry was a cottage industry in Japan, it was distributed throughout the civilian community even into their homes. I believe it was much the same in Germany.
Even apart from that, the Axis set the tone in the Thirties into the Forties with Rotterdam and Nanking. That was the treatment we could expect if we lost, so Queensbury Rules were not followed.
It was unrestricted war.