Had an invasion of Japan taken place, the death toll and carnage would have been much worse, more widespread, and who knows how post WWII Japan would have looked. We might have needed the Soviets help, and they might have taken all of Hokkaido....
日本*ピング* (kono risuto ni hairitai ka detai wo shirasete kudasai : let me know if you want on or off this list)
An invasion would’ve been impossible without more fire bombing and/or more nukes. Anyone who has seen pictures of Tokyo/Yokohama in July of 1945 should know how horrible this would have been for Japan.