> Why should it matter that China and the U.S. have incompatible political values? And what does that even mean?
Because people have moral values they care a lot about, and those are frequently reflected in their political systems. I don't know so much about China in that regard, but in the West those moral values certainly tend to be conceived in universalist terms.
> It's not like the two systems need to interface in ways where that matters. If you're trying to negotiate a treaty it doesn't really matter how the other country's delegation got their jobs.
Your kind of conceiving of the "interface" as some abstract thing up in the clouds. Sure, it probably doesn't really matter so much "how the other country's delegation got their jobs," but it certainly does matter what policies their government implements or positions its pursuing. In the case of the US and China, those definitely conflict in irreconcilable ways (e.g. over the status of Taiwan, civil liberties, etc.).
This sounds like the motive for religious war. Are we not tolerant enough to let other peoples have their own political systems?
It took a couple hundred years for Europeans to stop killing each other in the wake of the Reformation. Maybe we still haven't gotten over the instinct that somewhere, someone is doing it wrong and we have to do something about it.
> This sounds like the motive for religious war. Are we not tolerant enough to let other peoples have their own political systems?
You seem to be conflating morality with religion. There's overlap, but they're not the same.
> Maybe we still haven't gotten over the instinct that somewhere, someone is doing it wrong and we have to do something about it.
OK, see about that: are you tolerant enough to let your neighbor non-consensually beat his wife for being disobedient? Rape his kids? If you feel those things are wrong, do you think that's an instinct you should "get over"?
Because people have moral values they care a lot about, and those are frequently reflected in their political systems. I don't know so much about China in that regard, but in the West those moral values certainly tend to be conceived in universalist terms.
> It's not like the two systems need to interface in ways where that matters. If you're trying to negotiate a treaty it doesn't really matter how the other country's delegation got their jobs.
Your kind of conceiving of the "interface" as some abstract thing up in the clouds. Sure, it probably doesn't really matter so much "how the other country's delegation got their jobs," but it certainly does matter what policies their government implements or positions its pursuing. In the case of the US and China, those definitely conflict in irreconcilable ways (e.g. over the status of Taiwan, civil liberties, etc.).