technology improves there is less value in the labor of assembly. Not just in automotive but everywhere. Where there were once skilled machinists, welders and painters there are now a few robot programmers and a few people with skills that nearly anybody can learn in order to get parts from one station to the next. Yes, there are a few inspectors, etc but not the masses of skilled, value adding labor that there once was. Even if some new technology emerges that requires the equivalent of a 1960's machinist skill and knowledge why would a company do that function here when labor elsewhere is cheaper? It is very unlikely that the whatever that skill is would be uniquely American. In 20 years it is far more likely that Boeing will be building planes in China than some miracle game changing technology is being manufactured here. Cures for cancers, AI, VR, genetic engineered crops and animals, solar technology, carbon recapture, etc etc etc. Very, very possible to be conceived, designed, tested and developed here... and manufactured where the labor is cheaper. There is simply no reason to do it here.