Seldom does politics offer the rigor and certainty of science, but we have just witnessed a case that comes close. Tea Party leaders predicted that a shutdown strategy would result in mass uprising against Obamacare, forcing the political establishment to defund or delay it. In fact, Republicans were broadly blamed for overreach, and the law became (in some polls) more popular.

Conservatives who are not sobered are not serious. And those who insist that just a little more fortitude in the Senate would have turned the tide - causing at least six Democratic senators to switch their votes and the president to meekly accept defunding - have chosen to live in a pleasing political world of their own creation.

This is a serious setback for Republicans. It is not, however, the political apocalypse. The broader debate over Obamacare is favorable to its critics. Implementation problems increasingly seem structural, not technical. Americans are being compelled to join a system that was hastily designed, poorly tested and remains persistently dysfunctional.

And President Obama's recent political victory was largely empty of substance. The Republican Party conducted a nervous breakdown in public - and the president won the status quo, with a four-month extension of the sequestration.

Yet recent Republican problems are not temporary or cosmetic.

It is now clear that there is no functional majority in the House of Representatives.

Some Republicans blame Speaker John Boehner's passive leadership style. But the problem is not a lack of firmness or charisma. Recent divisions represent an escalation of Tea Party rhetoric and ambitions - not just an attempt to block Obamacare, but an accusation that other conservatives who oppose their approach are supporting Obamacare.

This is a strategic and tactical debate rather than a policy disagreement. But the result is no less bitter. Both sides of the GOP want to get rid of an unpopular law. One side believes in building a legislative majority and electing a president to overturn it; the other believes in making preposterous demands and blaming their Republican colleagues when these demands aren't fulfilled. Republican leaders, in turn, naturally view the Tea Party caucus as politically irrational and irresponsible. Boehner has not bridged this gap. Perhaps no one could.

Will the Tea Party be chastened by recent defeat? Not likely, or not for long. This conflict is certain to bleed over into the 2016 Republican presidential primaries. All the conditions for volatility will be present: voters embittered by recent defeats, a growing infrastructure of Tea Party institutions, a campaign-finance system easily influenced by ideologically eccentric billionaires.

The trends that helped elevate a series of politically unserious Republican candidates in 2012 - including Herman Cain and Michele Bachmann - have only grown stronger. Republican primary voters have a tendency to make more sober political choices in the end. But the process itself creates a durable image of radicalism and instability.

This leaves Republican governors as the most functional element of the party - and many are not only functional but impressive. They have the best prospect of carrying a tough critique of Obamacare while proposing a credible alternative. But the longing for a great leader is also a form of confession: that a divided party is in need of saving.

(c) 2013, Washington Post Writers Group

E-mail: michaelgerson@washpost.com