But we’re talking about voodoo economics here, so perhaps it’s not surprising that belief in the magical powers of tax cuts is a zombie doctrine: no matter how many times you kill it with facts, it just keeps coming back. And despite repeated failure in practice, it is, more than ever, the official view of the G.O.P.

Why should this scare you? On paper, solving America’s long-run fiscal problems is eminently doable: stronger cost control for Medicare plus a moderate rise in taxes would get us most of the way there. And the perception that the deficit is manageable has helped keep U.S. borrowing costs low.

But if politicians who insist that the way to reduce deficits is to cut taxes, not raise them, start winning elections again, how much faith can anyone have that we’ll do what needs to be done? Yes, we can have a fiscal crisis. But if we do, it won’t be because we’ve spent too much trying to create jobs and help the unemployed. It will be because investors have looked at our politics and concluded, with justification, that we’ve turned into a banana republic.

Of course, flirting with crisis is arguably part of the plan. There has always been a sense in which voodoo economics was a cover story for the real doctrine, which was “starve the beast”: slash revenue with tax cuts, then demand spending cuts to close the resulting budget gap. The point is that starve the beast basically amounts to deliberately creating a fiscal crisis, in the belief that the crisis can be used to push through unpopular policies, like dismantling Social Security.

Anyway, we really should thank Senators Kyl and McConnell for their sudden outbursts of candor. They’ve now made it clear, in case anyone had doubts, that their previous posturing on the deficit was entirely hypocritical. If they really do have the kind of electoral win they’re expecting, they won’t try to reduce the deficit  they’ll try to make it explode by demanding even more budget-busting tax cuts.