Yes, Dick Cheney was temporarily acting President.
I am not sure why you are bringing that up, though. It's a non sequitur.

Joe Biden has never been President, acting or otherwise.

You can just stop right there then.
Joe Biden has never been president.

But then the Chinese were subjugated by other Eurasians who decided not to be insular, but rather to plunder the world for its wealth.

Which is the point of the Fermi paradox - yes, maybe 99% of civilizations might retreat and huddle in Dyson spheres or whatever, but all it takes is one civilization to do otherwise and the galaxy is colonized in less than 1e6 years. That none has apparently done so is a datum whose explanation cannot help but be interesting.