I think one missing key aspect is: will the US be ever able to come to terms with _an authoritarian_ power being the dominant world power?
There was a lot of optimism around China (much like there is today with Japan) in the 2000's and early 2010's, but their continued lean towards authoritarianism and regional aggression (Taiwan, South China Sea, Philippines, etc) has definitely soured that view.
From a 50+ year historical standpoint it seems even more than philosophy that the two should get along.
Not confident in my understanding though, isn't there more to current politics than recent events and the last 30 years? Wondering if and suspecting there's something with more predictive value than online headlines and pundits.
Demographics clearly -- TFR types of analysis seem compelling, although that's on a longer time frame than current tensions.
Fundamental question is will US be ever able to come to terms with a world in which US is not the dominant world power?
Practically if you look at the British or Russians, it doesn't seem to make much difference to the lives of ordinary people, the losing of 'world power' status.