This was clearly true of the debt incurred to win World War II. Taxpayers were on the hook for a debt that was significantly bigger, as a percentage of G.D.P., than debt today; but that debt was also owned by taxpayers, such as all the people who bought savings bonds. So the debt didn’t make postwar America poorer. In particular, the debt didn’t prevent the postwar generation from experiencing the biggest rise in incomes and living standards in our nation’s history.

But isn’t this time different? Not as much as you think.

It’s true that foreigners now hold large claims on the United States, including a fair amount of government debt. But every dollar’s worth of foreign claims on America is matched by 89 cents’ worth of U.S. claims on foreigners. And because foreigners tend to put their U.S. investments into safe, low-yield assets, America actually earns more from its assets abroad than it pays to foreign investors. If your image is of a nation that’s already deep in hock to the Chinese, you’ve been misinformed. Nor are we heading rapidly in that direction.

Now, the fact that federal debt isn’t at all like a mortgage on America’s future doesn’t mean that the debt is harmless. Taxes must be levied to pay the interest, and you don’t have to be a right-wing ideologue to concede that taxes impose some cost on the economy, if nothing else by causing a diversion of resources away from productive activities into tax avoidance and evasion. But these costs are a lot less dramatic than the analogy with an overindebted family might suggest.

And that’s why nations with stable, responsible governments — that is, governments that are willing to impose modestly higher taxes when the situation warrants it — have historically been able to live with much higher levels of debt than today’s conventional wisdom would lead you to believe. Britain, in particular, has had debt exceeding 100 percent of G.D.P. for 81 of the last 170 years. When Keynes was writing about the need to spend your way out of a depression, Britain was deeper in debt than any advanced nation today, with the exception of Japan.

Of course, America, with its rabidly antitax conservative movement, may not have a government that is responsible in this sense. But in that case the fault lies not in our debt, but in ourselves.

So yes, debt matters. But right now, other things matter more. We need more, not less, government spending to get us out of our unemployment trap. And the wrongheaded, ill-informed obsession with debt is standing in the way.