One particularly nice detail in the piece, the kind of detail you could only get from talking to real survivors shortly afterwards, is the kinds of theories and rumors that were going around the day of/after the bomb. People thought the Americans had sprinkled gasoline and lit it on fire, or thought that there had been some kind of trick involving dusting the city with magnesium. The weird rumors remind me of the kind of stuff I heard on the day of 9/11.
I think the "why" would have been obvious to anyone -- there was an ongoing, active war in which both sides had been bombing each other and killing civilians, and Hiroshima was contributing significant production toward the war effort.
Having gone through Katrina and been deployed for Fukushima, I assure you, there is plenty of time for the survivors to contemplate all the questions. That is arguably part of the tragedy of survivorship: facing down all the questions, and knowing with cruel certainty there will be time to face them.
I also went through Katrina and the thing in this piece that reminded me the most of that experience was how people quickly became numb to the horror of their situation and dealt with things practically, one thing after the other. Or alternately became totally nonfunctional.
Eh, when the gadgets fell the US had been terror bombing Japanese cities for 10 months: "why" probably wasn't very pressing at that point. Burning Japanese civilians was simply an American thing to do at that point.
