It's clear that no amount of pussy-grabbing, vulgarity, racism, or spite will ever alienate Trump from his supporters. (In fact, those are the reasons they like him.)
But a self-inflicted, outright trade war with China?
The reason I think this holds some water beyond all the White Racial Resentment stuff is two fold. First, Americans have grown used to a Walmart lifestyle dependent on cheap shit from China and the rest of Asia. Given a few weeks, that could be over.
Second, China is (obviously) a lot smarter than Trump. They're going after agricultural goods from Red States like soybeans and hogs.
Again, this doesn't mean Trump is finished by a long shot. But it means he has to explain the benefits of a trade war that not even his advisers wanted.
If that's what it takes to get him out of office come 2020, so be it.