The borders were continuously shifting, but they did stay somewhat near a focal point for centuries.
The US meanwhile has an overseas empire for honestly no good reason.
Highly recommend the book “How to hide an empire” which talks about the American version of colonialism.
The reason for our overseas empire was to maintain our economic dominance.
If everyone voluntarily refused to touch boats and only trade oil for dollars we may have invested differently.
> The borders were continuously shifting, but they did stay somewhat near a focal point for centuries.
Ok? They were still an imperial power. Having a stable border for a little while doesn't affect that definition.
> The US meanwhile has an overseas empire for honestly no good reason.
https://en.wikipedia.org/wiki/Whataboutism