they went home?
didn’t we land a huge occupation force after they surrendered?
Operation Blacklist, the occupation of Japan, peaked at 350,000 troops at the end of 1945. Leaders estimated 500,000 to 1,000,000 Allied casualties if Operation Coronet (the second planned invasion of Honshu) lasted more than 90 days. So yes, most of them did go home.
Here's an interesting fact: in preparation for the anticipated invasion of Japan, 500,000 Purple Hearts were manufactured, and as of 2003 there were still 120,000 of them left after the Korean, Vietnam and all other conflicts involving American soldiers. Combat units in Iraq and Afghanistan had Purple Hearts on hand for immediate presentation to wounded soldiers in the field.
I don’t know how many were stationed in Japan but most got out. All I know is a lot of war-weary vets of the European theater were ready or in the process of deploying to the Pacific and lucked out. My Dad spent almost a year back in the states before he got out. I missed being a military brat by two months.
I expect enlistees had to serve out their time while draftees duty ended with the actual war.