I wonder however, if we shouldn't have used the two bombs on Kyushu... based on the fact that this was occurring (McArthur's doubts nothwithstanding):
From mid-July onwards, Ultra intercepts exposed a huge military buildup on Kyushu. Japanese ground forces exceeded prior estimates by a factor of four. Instead of 3 Japanese field divisions deployed in southern Kyushu to meet the 9 U.S. divisions, there were 10 Imperial Army divisions plus additional brigades. Japanese air forces exceeded prior estimates by a factor of two to four. Instead of 2,500 to 3,000 Japanese aircraft, estimates varied between about 6,000 and 10,000. One intelligence officer commented that the Japanese defenses threatened "to grow to [the] point where we attack on a ratio of one (1) to one (1) which is not the recipe for victory.
If our two nuclear bombs were detonated over the Japanese airfields in Kyushu (this assuming they could get into release range unmolested) would have annhilated a good portion of the residual air corps of Japan...both men and machines. What would THAT have done to their grim determination?