One piece of evidence comes from the relationship between job openings and unemployment. Normally these two numbers move inversely: the more job openings, the fewer Americans out of work. And this traditional relationship remains true if we look at short-term unemployment. But as William Dickens and Rand Ghayad of Northeastern University recently showed, the relationship has broken down for the long-term unemployed: a rising number of job openings doesn’t seem to do much to reduce their numbers. It’s as if employers don’t even bother looking at anyone who has been out of work for a long time.

To test this hypothesis, Mr. Ghayad then did an experiment, sending out résumés describing the qualifications and employment history of 4,800 fictitious workers. Who got called back? The answer was that workers who reported having been unemployed for six months or more got very few callbacks, even when all their other qualifications were better than those of workers who did attract employer interest.

So we are indeed creating a permanent class of jobless Americans.

And let’s be clear: this is a policy decision. The main reason our economic recovery has been so weak is that, spooked by fear-mongering over debt, we’ve been doing exactly what basic macroeconomics says you shouldn’t do — cutting government spending in the face of a depressed economy.

It’s hard to overstate how self-destructive this policy is. Indeed, the shadow of long-term unemployment means that austerity policies are counterproductive even in purely fiscal terms. Workers, after all, are taxpayers too; if our debt obsession exiles millions of Americans from productive employment, it will cut into future revenues and raise future deficits.

Our exaggerated fear of debt is, in short, creating a slow-motion catastrophe. It’s ruining many lives, and at the same time making us poorer and weaker in every way. And the longer we persist in this folly, the greater the damage will be.