Oh, and let me give a special shout-out to “centrist” pundits who won’t admit that President Obama has already given them what they want. The dialogue seems to go like this. Pundit: “Why won’t the president come out for a mix of spending cuts and tax hikes?” Mr. Obama: “I support a mix of spending cuts and tax hikes.” Pundit: “Why won’t the president come out for a mix of spending cuts and tax hikes?”

You see, admitting that one side is willing to make concessions, while the other isn’t, would tarnish one’s centrist credentials. And the result is that the G.O.P. pays no price for refusing to give an inch.

So the supercommittee will fail — and that’s good.

For one thing, history tells us that the Republican Party would renege on its side of any deal as soon as it got the chance. Remember, the U.S. fiscal outlook was pretty good in 2000, but, as soon as Republicans gained control of the White House, they squandered the surplus on tax cuts and unfunded wars. So any deal reached now would, in practice, be nothing more than a deal to slash Social Security and Medicare, with no lasting improvement in the deficit.

Also, any deal reached now would almost surely end up worsening the economic slump. Slashing spending while the economy is depressed destroys jobs, and it’s probably even counterproductive in terms of deficit reduction, since it leads to lower revenue both now and in the future. And current projections, like those of the Federal Reserve, suggest that the economy will remain depressed at least through 2014. Better to have no deal than a deal that imposes spending cuts in the next few years.

But don’t we eventually have to match spending and revenue? Yes, we do. But the decision about how to do that isn’t about accounting. It’s about fundamental values — and it’s a decision that should be made by voters, not by some committee that allegedly transcends the partisan divide.

Eventually, one side or the other of that divide will get the kind of popular mandate it needs to resolve our long-run budget issues. Until then, attempts to strike a Grand Bargain are fundamentally destructive. If the supercommittee fails, as expected, it will be time to celebrate.