Belton Ag said:
Taking this whole theme a little further… was the fall of Japan, in the long run, a catastrophe for the US?
We didn't get involved in the Chinese Civil War in the aftermath of the fall of Japan and basically stood back and let the communists defeat the Kuomintang and take over China. In hindsight, this was probably even more impactful to us than the fall of the Soviet Union. In the wake of this, we were led into conflicts in Korea and Vietnam and the rise of China as the main economic and geopolitical rival seems to overshadow the Cold War. In China is now what the Soviet Union could never be.
From 1941 to 1945 the US rooted out Japan, island by island, country by country, at the cost of 200,000 American lives, so much of our blood and treasure. Only to see it all fall, within a generation, into the orbit of the Soviet Union, who barely fired a shot in the Pacific Theater outside of the invasion of Manchuria. What a bitter pill to swallow. How much of this played into our decision to go into Vietnam? All three presidents after Eisenhower served in the Pacific Theater. Surely that played a role.
If by "fall" you mean the Pacific War and having to fight Japan, yes it was a wasteful disaster that better diplomacy on both sides could have avoided. But not by 1941. The time was earlier. But as you almost certainly know, with our reconstruction, Japan emerged as a powerful ally with their yards proving vital even as soon as the Korean War and especially after in Viet Nam. They certainly didn't fall into the orbit of the Soviet Union (but maybe you mean Korea or even China? I think from context that is what you mean) So in that sense not a "fall" in that Japan didn't fall to communism or anything like that. Which brings us to the interesting thing you called attention to.
I hadn't thought much about the fact that if we don't go to war with Japan it would somewhat mean we are indeed there at strength to help Nationalist China and maybe avert the course of the Chinese Civil War. However, there is a big question mark which is why hadn't dwelt on that. Japan had invaded China and was carving off pieces in the style of the European powers a century earlier. As mentioned earlier, the army occupies IndoChina to open another front. Now if you say we don't have the Pacific War, then Sino-Japanese War just goes on full blast, but with the Japanese getting increasingly moribund (China had become an Afghanistan/Soviets mire for the Japanese by 1942) . Depending on how that winds up (probably with a Japanese withdrawal to and firm holding of Manchuria which they had partly rebuilt and was the only thing totally unwilling to cede up - the Crimea equivalent if you will) --depending on that, we know enough about Mao and Chiang both to know their civil war DOES resume. But this time it is with an America not put through the Pacific War. So you believe that America would have acted firmly enough to make sure Nationalist China wins? You may be right that China's rise into a communist superpower is actually the most impactful event, but would that be realized then.