My very first job after college was in a Union Carbide steel mill in Sheffield, ALA. Are there still enough Americans who know what a steel mill is?
They're not all retired or passed away, not yet. We've got a window of about a decade by my estimation, before the trained workforce remainder is lost for good and would be starting completely from scratch. A lot of these people are hurting or are at least in reduced circumstance, so it would be a very welcome thing. Able-bodied retirees I'm sure are more patriotic than the norm and would answer the call to help their country and make a little money while they're at it, too. Come back, teach the next generation, get us back up and running. We'd owe them a debt of gratitude and they'd be thrilled.