I get that, but I was thinking the US is weaker after a longer and bloodier civil war, and by the time they feel up to the tast, they are hesitant because the AngloJapanese Alliance has been formed. The US instead focuses on the Americas and Africa to build up and eventually go to war. I thought maybe isolationism would eventually win out, however, which is why the US doesn't get involved in the world wars ITTL.
Well, that makes sense too. I mean, they would have to fight in Canada and the Caribbean, which is easy.
But things get more complicated if we think that they would have to invade British and Japanese possessions single-handedly in Eurasia. And trying to intimidate another country into letting them put forward bases would only make them look worse.
(Negotiating is out of the question because the UK can double down on any offer the US makes, and back it up with the threat of the Royal Navy if necessary.)
Giving them the Belgian Congo, I guess it was an agreement "We don't want any of us to keep this territory, but we don't want it to just be empty either. So we're going to give it to this guy, who none of us particularly dislike"