Leaders who act against the interests of their constituents get voted out. I can’t imagine a majority of US politicians holding the thought that American jobs must be sacrificed for the good of the world. The less convoluted reason is that Corporations make a ton more profit by manufacturing overseas and have directed their lobbying dollars into either making politicians look the other way or prohibit them from taking meaningful efforts to save domestic manufacturing.

When there's the "America is the cause of all evil" guilt (slight exaggeration), you can. A belief that what you do is moral can get people to align against their own interests.

Just because it’s a possibility doesn’t mean that it’s actually happening. If it was this would certainly be covered by the media, Politicians would have a policy platform to address this etc. There doesn’t seem to be any evidence to indicate that’s what’s happening.