So, what do you think about those Medicare numbers? What, you haven’t heard about them? Well, they haven’t been front-page news. But something remarkable has been happening on the health-spending front, and it should (but probably won’t) transform a lot of our political debate.

The story so far: We’ve all seen projections of giant federal deficits over the next few decades, and there’s a whole industry devoted to issuing dire warnings about the budget and demanding cuts in Socialsecuritymedicareandmedicaid. Policy wonks have long known, however, that there’s no such program, and that health care, rather than retirement, was driving those scary projections. Why? Because, historically, health spending has grown much faster than G.D.P., and it was assumed that this trend would continue.

But a funny thing has happened: Health spending has slowed sharply, and it’s already well below projections made just a few years ago. The falloff has been especially pronounced in Medicare, which is spending $1,000 less per beneficiary than the Congressional Budget Office projected just four years ago.

This is a really big deal, in at least three ways.

First, our supposed fiscal crisis has been postponed, perhaps indefinitely. The federal government is still running deficits, but they’re way down. True, the red ink is still likely to swell again in a few years, if only because more baby boomers will retire and start collecting benefits; but, these days, projections of federal debt as a percentage of G.D.P. show it creeping up rather than soaring. We’ll probably have to raise more revenue eventually, but the long-term fiscal gap now looks much more manageable than the deficit scolds would have you believe.