China benefits from conflict with America. It foments exactly this kind of reactionary nationalism.

The US during the Cold War could rally around large national programs (e.g. space race) and wars (e.g. Vietnam) because there was a foreign enemy. That enemy could be foreign actor (Russia) or an idea (communism) or a person (Saddam, for example.)

The spirit of "do your part" is deeply appealing to our core desire to form tribe. The strongest sense of Us comes from a Them.