In contrast to the United States, I am not familiar with any empire that has every existed that responded to erstwhile allies by threatening to pull their troops from the ally’s land.
America has, as an ‘Imperial’ power, been quite literally, the single most benevolent power in the history of Earth.
Which makes the self-destruction called “free trade”, all the more tragic.
After they set up “our” gangsters to run the place. Naturally they don’t want the troops to leave or their people will exact revenge.
Note: I’m love our dear country for the wonderful things we have done for the world. But when we stink, I personally like to call the stink what it is.