They sort of fall into the catch-all bucket of "immigrants" which tends to have a different face depending on where you are, but is almost universally brown. For a while "ISIS is sending fighters across the border" was a right wing talking point. Even when you hear trump talking about it, the Muslim ban or whatever, it's always in this context.

In general "freedom of religion" is one of those pieces of the American civil religion that is pretty well cemented, in that so long as you're american/assimilated your faith doesn't really matter. Muslims abroad are an entirely different issue for this reason.

Islamophobia was a huge problem particularly after 9/11 but sinophobia seems to be the bigotry flavor of choice at the moment. All that said, nobody who isn't white in the US really gets a fair shake.