Same as happened in the Europeans' Asian colonies. (Having better weapons is not the same as having a better civilisation.)
I see the US in a hundred years as being much like Britain today. Both having a sort of faded prestige, but no real power, because they can no longer extract wealth from other nations. Once Britain lost India in the 1940s, it lost the 'Jewel in the Crown', the source of trillions of dollars worth of British wealth that had sustained Britain for a couple of hundred years.
I made no claims about which civilizations were "better" or "more advanced". Those words don't mean very much.
The WHOLE of the West (US, 5-Eyes, Europe) COMBINED is only about 70% the size of China ALONE in terms of both population and manufacturing capacity.
We're not going to win the next 'big one'.
Up till the 1400s, the West was a very minor player in the world. The 'big boys' of the time were India and China. Recall Marco Polo's amazement at the riches and technology of 'Cathay'.
As India and China regain their traditional places in the world, the West will 'collapse' back to its minor, pre-1400 role in the world.