It looks like an emperor's new clothes scenario to me. People agree with each other that the US should manufacture more because they have picked up that that's the respectable answer; not because they see any actual sense in it.

Or maybe it's some sort of nostalgia. I guess people used to say that more people should work in agriculture, because that was somehow their idea of a proper, wholesome country.

People who play medievalist games somehow never pretend to be serfs or farm-hands.

There are a few areas where you would want manufacturing in the country. Defense, some medical supplies, ... Just in case things go bad, you'd want some capacity, some expertise in the country to be less dependent. You'd spend extra resources just in case, just to be safe. But it's never a rational end in itself.