The tea party, the most welcome political development since the Goldwater insurgency in 1964, lacks only the patience necessary when America lacks the consensus required to propel fundamental change through our constitutional system of checks and balances. If Washington's trajectory could be turned as quickly as tea partyers wish -- while conservatives control only one-half of one of the two political branches -- their movement would not be as necessary as it is. Fortunately, not much patience is required.

The Goldwater impulse took 16 years to reach fruition in the election of Ronald Reagan. The tea party can succeed in 16 months by helping elect a president who will not veto necessary reforms. To achieve that, however, tea partyers must not help the incumbent achieve his objectives in the debt-ceiling dispute.

One of those is to strike a splashy bargain involving big -- but hypothetical and nonbinding -- numbers. This would enable President Obama to run away from his record and run as a debt-reducing centrist. Another Obama objective is tax increases that shatter Republican unity and dampen the tea party's election-turning intensity. Because he probably can achieve neither, he might want market chaos in coming days so Republicans henceforth can be cast as complicit in the wretched recovery that is his administration's ugly signature.

Mitch McConnell's proposal would require Obama to make three requests for additional debt-ceiling increases. Each time he would be required to recommend commensurate spending reductions. Concerning them, Congress would, of course, retain its constitutional power to do what it wishes.

Thanks largely to the tea party, today, more than at any time since Reagan's arrival 30 years ago, Washington debate is conducted in conservatism's vocabulary of government retrenchment. The debt-ceiling vote, an action-forcing mechanism of limited utility, has at least demonstrated that Obama is, strictly speaking, unbelievable.

Five months ago he submitted a budget that would have accelerated indebtedness, and that the Democratic-controlled Senate rejected in May, 97-0. Just three months ago he was demanding a "clean" increase in the debt ceiling, containing nothing to slow the spending carousel. Now he calls for "the largest possible" debt-reduction deal. Today, he says "if you look at the numbers, then Medicare in particular will run out of money and we will not be able to sustain that program no matter how much taxes go up." Last year he advertised Obamacare as a sufficient reform of health care. He denounces Republicans as uncompromising regarding tax increases, but vows "I will not accept" a deal that does not increase taxes.

Obama's rhetorical floundering is the sound of a bewildered politician trying to be heard over the long, withdrawing roar of ebbing faith in a failing model of governance. From Greece to California, with manifestations in Italy, Spain, Portugal, Ireland, Illinois and elsewhere, this model is collapsing. Entangled economic and demographic forces are refuting the practice of ever-bigger government financed by an ever-smaller tax base and by imposing huge costs on voiceless future generations.

Richard Miniter, a Forbes columnist, is right: "Obama is not the new FDR, but the new Gorbachev." Beneath the tattered, fading banner of reactionary liberalism, Obama struggles to sustain a doomed system. Democrats' dependency agenda -- swelling the ranks of government employees, multiplying government-subsidized industries, enveloping ever-more individuals in the entitlement culture -- is buckling under an intractable contradiction: It is incompatible with economic growth sufficient to create enough wealth to feed the multiplying tax eaters.

Events are validating the tea partyers' arguments. Time is on their side -- but not on America's, unless the impediment to reform is removed in 16 months.