It's hard to believe about such a polite people who make such great cars and cameras, but the wartime Japanese were really over-the-top wacky. Some of them positively loathed cities, also money, electricity, internal combustion - a hundred thousand or so people meant absolutely nothing to them. Mainly, the bomb got the emperor's attention.
There is also the matter of the invasion. Hitting Kyushu was technically tricky, considering beach and surf conditions and so forth. They were planning on sending in 4 million females with sharpened screwdrivers and such. I wonder if we could have off-loaded enough ammo in time. They had a first-rate bio-weapons program. It's almost surprising the never used them on our Pacific bases, or even California. And that's not everything by a long shot. Like somebody else once said, thank God for the atom bomb.