Bear in mind that G.O.P. leaders don’t actually care about the level of debt. Instead, they’re using the threat of a debt crisis to impose an ideological agenda. If you had any doubt about that, last week’s tantrum should have convinced you. Democrats engaged in debt negotiations argued that since we’re supposedly in dire fiscal straits, we should talk about limiting tax breaks for corporate jets and hedge-fund managers as well as slashing aid to the poor and unlucky. And Republicans, in response, walked out of the talks.

So what’s really going on is extortion pure and simple. As Mike Konczal of the Roosevelt Institute puts it, the G.O.P. has, in effect, come around with baseball bats and declared, “Nice economy you have here. A real shame if something happened to it.”

And the reason Republicans are doing this is because they must believe that it will work: Mr. Obama caved in over tax cuts, and they expect him to cave again. They believe that they have the upper hand, because the public will blame the president for the economic crisis they’re threatening to create. In fact, it’s hard to avoid the suspicion that G.O.P. leaders actually want the economy to perform badly.