As he explained it today, President Obama's policy toward Libya consists of two apparently unconnected parts.
One part is regime change, getting Qaddafi out. But those bombs over Benghazi and elsewhere, including the British missile attack on Qaddafi's own compound, are not about that. No, they are for the sole purpose of preventing the humanitarian calamity that Qaddafi seemed ready to unleash last week. It was apparently ok for Qaddafi's forces to crush the rebels, but just not as savagely as he threatened.
As for getting him out of power, that will be left to what Obama called a -- wide range of other tools to isolate and pressure him into stepping down.
Now all of this may work out. Qaddafi may be brutal but he is not brave and nothing gets his attention like bombs on his compound, as Ronald Reagan proved back in 1986. Qaddafi basically vanished for two years. The current allied attacks, whatever their ostensible purpose, may also allow the rebels to gain the upper hand and hasten Qaddafi's downfall.
But if neither of these outcomes occurs, there's no sign the president is prepared for further tougher steps to accomplish his stated goals. His emphasis instead is on how brief this mission will be, how limited and how soon the U.S. leadership role will be ended.
Failure, it seems in this case, is an option.