They could kick the US out at anytime. They won't because they want the US to be there. Not the standard definition at all.

US bases pay rent on land, employ locals, and will instantly shut down if the host country asks them to (after having been invited to enter to begin with). Of course there are cold war era exceptions, but this is the norm:

> The U.S. base at the Bishkek airport had become a regular source of criticism from various Kyrgyz politicians and, with heavy Russian influence, it also closed in 2014.

https://www.rferl.org/a/u-s-military-bases-in-central-asia-p...

Again, doesn't sound like any Empire i've read about in a history book.