President Obama identifies what he thinks was his biggest mistake as president:

President Barack Obama said the worst mistake of his presidency was a lack of planning for the aftermath of the 2011 toppling of Libyan dictator Moammar Gadhafi.

“Probably failing to plan for the day after what I think was the right thing to do in intervening in Libya,” he said in a Fox News interview aired Sunday.

I don’t think this was Obama’s biggest mistake, but it is revealing that he remains convinced that this lack of post-Gaddafi planning is worse than the far greater error of intervening in Libya in the first place. As we saw last week, this has become the self-serving rallying cry of Libyan war supporters. The only error interventionists are capable of recognizing is that of doing “too little.” They can’t admit that the intervention itself is a mistake without fully acknowledging their bad judgment in supporting it.

It is important to remember that the failure to plan for the aftermath of regime change in Libya was central to the administration’s case for intervention in the spring of 2011. The U.S. and its allies weren’t going to plan for post-Gaddafi Libya because they insisted that the war would be nothing like Iraq, and therefore there would be no attempt to police or stabilize Libya for years after the initial campaign was over. More to the point, the official U.S./NATO line was that the intervention wasn’t aimed at regime change. Why plan for post-Gaddafi Libya when we were supposedly not trying to overthrow the regime? Libyan war supporters also said that Libya wouldn’t need the U.S. and its allies to assume such a role, and no one was going to volunteer for that role in any case.

Obama knew at the time that there was absolutely no political support in the U.S. or anywhere else for a prolonged mission in Libya. Promising not to start an open-ended mission in Libya is what made the war politically viable here at home. The public would tolerate bombing for eight months and then writing off the country, but there wouldn’t be similar patience for a new occupation in yet another Muslim country with the costs and casualties that would likely entail.

It was not an oversight by the intervening governments when they left Libya to its own devices. That was part of the plan, such as it was, from the very beginning. So it is hard to take Obama seriously when he faults himself for not committing the U.S. to a larger, costlier role in Libya when he and the other allied leaders deliberately decided against doing that. They made that decision because they wanted a low-risk intervention on the cheap, and they certainly weren’t prepared to make a long-term commitment to police and rebuild Libya. But they were willing to help throw the country into chaos and to destabilize the surrounding region and declare victory when the regime change they supposedly weren’t seeking had been achieved.