T o many, America’s industrial heartland may look like a place mired in the economic past—a place that, outcompeted by manufacturing countries around the world, has too little work to offer its residents. But things look very different to Karen Wright, the CEO of Ariel Corporation in Mount Vernon, Ohio. Wright’s biggest problem isn’t a lack of work; it’s a lack of skilled workers. “We have a very skilled workforce, but they are getting older,” says Wright, who employs 1,200 people at three Ohio factories. “I don’t know where we are going to find replacements.” That may sound odd, given...