What if one day the United States holds the immigrant rich in China?

Because their nationality is the United States, their status is a minority in the United States.

Here is a rhetorical question: If there is a war between China and Russia, will China take Russians from one of the 56 ethnic groups as hostages?

Think for yourself.

Hehe, one more thing: there were many Beijing soldiers in the self-defense counterattack against Vietnam.