“Even if it takes a change to the law, the president should honor the commitment the federal government made to those people and let them keep what they got.” – Bill Clinton, Nov. 12

So the former president asserts that the current president continues to dishonor his “you like your plan, you can keep your plan” pledge. And calls for the Affordable Care Act to be changed, despite furious White House resistance to the very idea.

Coming from the dean of the Democratic Party, this one line marked the breaching of the dam. It legitimized the brewing rebellion of panicked Democrats against Obamacare. Within hours, that rebellion went loudly public. By Thursday, President Obama had been forced into a rear-guard holding action, asking insurers to grant a one-year extension of current plans.

The damage to the Obama presidency, however, is already done. His approval rating has fallen to 39 percent, his lowest ever. And, for the first time, a majority consider him untrustworthy. That bond is not easily repaired.

At stake, however, is more than the fate of one presidency or of the current Democratic majority in the Senate. At stake is the new, more ambitious, social-democratic brand of American liberalism introduced by Obama, of which Obamacare is both symbol and concrete embodiment.

Precisely when the GOP was returning to a more constitutionalist conservatism committed to reforming, restructuring and reining in the welfare state (see, for example, the Paul Ryan Medicare reform passed by House Republicans with near unanimity), Obama offered a transformational liberalism designed to expand the role of government, enlarge the welfare state and create yet new entitlements (see, for example, his call for universal preschool in his most recent State of the Union address).

The centerpiece of this vision is, of course, Obamacare, the most sweeping social reform in the last half-century, affecting one-sixth of the economy and directly touching the most vital area of life of every citizen.

As the only socially transformational legislation in modern American history to be enacted on a straight party-line vote, Obamacare is wholly owned by the Democrats. Its unraveling would catastrophically undermine their underlying ideology of ever-expansive central government providing cradle-to-grave care for an ever-grateful citizenry.

For four years, this debate has been theoretical. Now it’s real. And for Democrats, it’s a disaster.

It begins with the bungled rollout. If Washington can’t even do the website – the literal portal to this brave new world – how does it propose to regulate the vast ecosystem of American medicine?

Second, arrogance. Five million freely chosen, freely purchased, freely renewed health care plans are summarily canceled. Why? Because they don’t meet some arbitrary standard set by the experts in Washington.

For all his news conference gyrations about not deliberately deceiving people with his “if you like it” promise, the law Obama so triumphantly gave us allows you to keep your plan only if he likes it. That’s the very definition of paternalism.

Lastly, deception. The essence of the entitlement state is government giving away free stuff. Hence Obamacare would provide insurance for 30 million uninsured, while giving everybody tons of free medical services – without adding “one dime to our deficits,” promised Obama.

This being inherently impossible, there had to be a catch. Now we know it: hidden subsidies. Toss millions of the insured off their plans and onto the Obamacare “exchanges” where they would be forced into more expensive insurance packed with coverage they don’t want and don’t need – so that the overcharge can be used to subsidize others.

The reaction to the incompetence, arrogance and deception has ranged from ridicule to anger. But more is in jeopardy than just panicked congressional Democrats. This is the signature legislative achievement of the Obama presidency, the embodiment of his new entitlement-state liberalism. If Obamacare goes down, there will be little left of its underlying ideology.

Perhaps it won’t go down. Perhaps the web portal hums beautifully on Nov. 30. Perhaps they’ll find a way to restore the canceled policies without wrecking the financial underpinning of the exchanges.

Perhaps. The more likely scenario, however, is that Obamacare does fail. It either fails politically, renounced by a wide consensus that includes a growing number of Democrats. Or it succumbs to the financial complications (the insurance “death spiral”) of the very amendments desperately tacked on to save it.

If it does fail, the effect will be historic. Obamacare will take down with it more than Mary Landrieu and Co. It will discredit Obama’s new liberalism for years to come.

© 2013, The Washington Post Writers Group