The American empire is commercial. Americans are hawking their products all over the world.
Hawking a lot of military product around the world as well - with plenty of string attached.
And of course, a Navy that has to police the world to keep commerce safe, right? And since we’re already around, might has well pitch in and help in a crisis. And hey, if we had a ‘crisis’ over there, it might help these donors, or recalcitrant societies that aren’t respectful enough, and...
America has lost it’s way, and will fall because of it.