Long-term, I've actually not been concerned about American manufacturing for a while now. Why is overseas manufacturing cheap? Primarily, cheap labor. When does that cease to be an advantage? When labor is no longer a significant cost in manufacturing. We're getting there pretty quickly, and IMHO robotics has only recently (i.e., last two or three years) taken off, which should be able to continue the increased-productivity-per-human trend for a while yet.
Bad time to become an assembly line worker. Good time to get into robotics for manufacturing, probably.
I had a contract job in a tool & die facility a couple of years ago. It wasn't a factory, it was a "build-to-order" facility that had a wide variety of equipment in various places and they needed better tracking of their jobs and such. I didn't mention this to anyone, but I was struck by how much work was being done that could be automated in the near future. Tens of jobs dedicated solely to moving things around, which robots are going to be able to take over in the 5 year timeframe. Another tens of jobs that involve placing a metal part just so in a press and pushing two buttons (two so you have to use both hands). QA can't be replaced with robots entirely, but it could be helped. The bulk of the people on the floor were not doing things that required human judgment, even for human-class vision or human-class pathfinding. The future is basically now.