there is a lot more going on between japan and the us even before ww2. for starters japan's south manchuria railway company basically became a joint venture in 1905, when japan started pushing into shandong in the 1920s the us starts doing diplomatic nosedives to try and protect the railways. the branch of the ija that was stationed in manchuria was called the kwantung army, they were a general army that had independent command of itself. the kwantung army never fought the us. after ww2 and after macarthur left japan the us (cia) starts putting 'ija' officials in every single office in japan, including media. even the guy who originally founded things like toei were former ija. and nobusuke kishi the guy who created the system of government japan uses today was the head official at manchuria, he ran their economic policy and was running 5 year plans on the country. basically labor death camps with 40% mortality rates. it's absolutely ludicrous just how many of these officials were 'de-purged' back into japan during the reverse course, and this never changed the ldp is still in power to this day.
United States