Associate editor

The promise and the apology are the bookends of effective politics. President Obama has, tragically and perhaps irreparably, flubbed both.

Overpromising is every politician’s temptation, every journalist’s gotcha, every political opponent’s handy club. A chicken in every pot. Read my lips. On the campaign trail, nuance is an unwelcome intruder.

Still, all political promises are not created equal. Most are campaign detritus, easily made and just as quickly forgotten. Click on any fact-checking scorecard of Obama promises: End no-bid contracts over $25,000? Seek to negotiate a political agreement on Cyprus? Support a tax deduction for artists? Who knew? Who remembers?

Likewise, all political promise-breaking is not equally devastating. Cynical voters assume, even accept, a certain level of calculated, built-in betrayal.

One category of breakable political promise is the aspirational, high-toned pledge. You can promise and fail to be a uniter, not a divider , or to change the tone in Washington without voters dinging you for attempting the impossible.

Another category of breakable promise is the one the politician demonstrably tried but failed to keep, for reasons outside his control. For Obama, the classic of this genre is the pledge to close the prison at Guantanamo Bay, Cuba, stymied by congressional refusal to let him transfer detainees to American soil.

The promise you can’t break without suffering significant political damage is one that is central to your platform and within your capacity to deliver.

Such as, “If you like your insurance plan, you will keep it.” This repeated promise was foolhardy on its face. You can’t renovate the kitchen without suffering some disruption. Same for health care.

Indeed, the now-famous grandfather clause, allowing insurers to continue to offer substandard plans that were in place as of March 2010, was a conscious effort to alleviate such disruption. Some Obama advisers argued against the grandfather clause because they thought everyone should be in the new exchanges; the president, acutely conscious of his promise, wanted existing plans protected.

But given the churning nature of the individual market — most people don’t keep coverage for long — this protection was inherently limited and destined to evaporate.

That the administration knew this and failed to anticipate the inevitable outcry is political malpractice of the highest order. That policyholders who received cancellation notices didn’t have a functional Web site on which to seek alternatives makes that preexisting condition exponentially worse.

Which brings us to the art of the political apology. As with the spousal apology, the longer you wait, the worse it is. Obama’s first fault was in chiding people for misunderstanding him: “What we said was you could keep it if it hasn’t changed since the law was passed.”

His second misstep was resorting to the politician’s favorite dodge: the non-apology apology, conditional and passive. I’m sorry if anyone was offended. Mistakes were made. “I am sorry that they, you know, are finding themselves in this situation based on assurances they got from me,” Obama told NBC’s Chuck Todd. What does that even mean?

Third, Obama’s actual apology was for the wrong thing. “Obviously, we didn’t do a good enough job in terms of how we crafted the law,” he told Todd. “That’s something that I regret.”

But the problem wasn’t the crafting — for the law to work, inadequate policies have to end sometime — it was the misleading selling and botched implementation.

“We put a grandfather clause into the law, but it was insufficient,” Obama said Thursday. “My working assumption was that . . . the universe of folks who potentially would not find a better deal in the marketplaces, the grandfather clause would work sufficiently for them. And it didn’t.”

And that working assumption was based on . . . ? Obviously not the administration’s own estimates that two-thirds or more of people in the individual marketplace would not be grandfathered in.

Belatedly, with congressional Republicans pouncing and Democrats threatening to bolt, Obama on Thursday proffered a supposed (it depends on the kindness of insurers and state insurance commissioners) and temporary (one-year) fix. By then, the exchanges should be functional, but will premiums climb higher as healthier people stick with existing plans?

Listening to the president Thursday was painful. He acknowledged the need “to win back some credibility.” He “fumbled the rollout” of health care. He is “letting . . . down” congressional Democrats who took the risk of supporting Obamacare. Although he’s sometimes been “slapped around a little bit unjustly,” the president said, “This one’s deserved, all right? It’s on us.”

Can he recover? I’m sorry to say: I’m not at all confident.

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