No way Japan would have surrendered had the US gone ahead with a land invasion. The US (rightly) believed that Japan would fight to the very last man.
The only problem is that by 1945, there was literally nothing left for the people back home on the mainland to fight with. Nearly every scrap of metal had been confiscated from all but the rich. People on the mainland would have been fighting with bamboo brooms and sticks - literally. I have first-hand stories - my ex gf’s grandfather told me about his experiences in the war. He was one of only two or three survivors (or was he the lone survivor? Can’t remember) of his company to make it back from a campaign in the Philippines. He was wounded, and got discharged. He talked about having to steal food from local homes in the Philippines the last few weeks. How he came back to Japan, only to find conditions actually worse.
And, my fiance’s grandfather is 93 years old, as a native Korean he was brought to Japan to work (i.e., slave labor) in the 1930s. As near as we can make out, he was being trained to fight by his army leaders - who were getting younger and younger - in 1944. They were issued guns, but didn’t have any bullets. So there was no actualy target practice. Training consisted of lying down on the ground, pointing your gun at a target, pulling the trigger, and saying ‘Pow!’.
Had the US government fully understood just how easily they could have taken the mainland with minimal casualties on both sides, they may well have re-thought the bomb. Hindsight’s 20-20, obviously - and after the ferocious battles fought in islands across the Pacific, the US stance is understandable.
I’ve worked in Japan on and off for the better part of 20 years. Every Japanese to a person that I’ve talked to about this issue plays up the ‘Japan as a victim of WWII’ because of the bomb - as one observer noted, 'we see what the world did to Japan, we don’t see so much what Japan did to the world.
But each person I’ve talked to also acknowledges that Japan would have in fact fought - if you can call people armed with bamboo rakes ‘fighting’ - to the man. Removing the Emperor would likely have caused riots. A friend of mine noted that they no longer let their grandfather go to see live sumo anymore, because on occasion the Emperor or someone from the royal family shows up, and it’s an embarrasing scene with the grandfather bowing and banzai-ing and so forth the entire time.
Nagasaki is hard to ‘defend’, as it were. The government knew that three days wasn’t near enough time for the Japanese government to fully comprehend what had happened. Survivors in Hiroshima didn’t fully understand for many, many days that the damage they were seeing was spread across the entire city, not just their local neighborhoods. Japan’s domestic infrastructure was already pretty much in shambles, the Hiroshima bomb made it all but impossible for information to get in or out of the city. Had the government had a bit more time, Nagasaki was likely un-necessary. Here, I do believe it is the case of the US government being influenced by its desire to ‘try out’ a second, different type of bomb from the one that was dropped on Hiroshima.
I’ve always wondered if the US military couldn’t have invited some Japanese diplomats to watch while they obliterated some tiny un-inhabited island, and let the diplomats take the message home. Some Japanese people I’ve talked to suggested that it wouldn’t have made any difference; the Japanese military would have preferred being wiped out to the ‘shame’ of ‘defeat’.
I’ve also long wondered if the US would have been as quick to drop a bomb on Germany if the war had been ongoing. Given the US’ strong pro-Europe history, I have my doubts, but of course no cites or facts to back it up.
