First, nothing is carved in stone, and despite narratives about moral obligations and the clearly detestable foe, Libya is in civil war. Gaddafi does have his supporters and some of them are clearly willing to die for the cause. As we've seen in Afghanistan, intervening on behalf of one side in a civil war is does not necessarily mean that things will work out to our advantage.
Second, no matter how clear cut the cause seems and how many times Western forces declare that they won't put boots on the ground (minus the special forces already there) and limit their involvement air support, these exercises tend to creep.
Third, it is probably best to consider the immediate halt of Gaddafi's advance by airstrikes as a much needed but temporary reprieve for victims of his onslaught. All that the coalition jets have done is prevent a massacre by Gaddafi's forces, but the country is still in civil war and these things move in non-linear fashion. Another week or twenty, and circumstances might change. A major component of destroying an opposing army involves the destruction of critical infrastructure such as power grids, highways, phone systems, airfields, docks, etc. We saw what happened in Iraq after the bombers were done and there's nothing to suggest the destruction of Libyan infrastructure, a key driver of social stability, won't also lead to a humanitarian emergency and/or an exacerbation of the conflict.
The ever critical Robert Fisk elaborates.
And what if we are simply not in time, if Gaddafi's tanks keep on rolling? Do we then send in our mercenaries to help the "rebels". Do we set up temporary shop in Benghazi, with advisers and NGOs and the usual diplomatic flummery? Note how, at this most critical moment, we are no longer talking about the tribes of Libya, those hardy warrior people whom we invoked with such enthusiasm a couple of weeks ago. We talk now about the need to protect "the Libyan people", no longer registering the Senoussi, the most powerful group of tribal families in Benghazi, whose men have been doing much of the fighting. King Idris, overthrown by Gaddafi in 1969, was a Senoussi. The red, black and green "rebel" flag – the old flag of pre-revolutionary Libya – is in fact the Idris flag, a Senoussi flag. Now let's suppose they get to Tripoli (the point of the whole exercise, is it not?), are they going to be welcomed there? Yes, there were protests in the capital. But many of those brave demonstrators themselves originally came from Benghazi. What will Gaddafi's supporters do? "Melt away"? Suddenly find that they hated Gaddafi after all and join the revolution? Or continue the civil war?
And what if the "rebels" enter Tripoli and decide Gaddafi and his crazed son Saif al-Islam should meet their just rewards, along with their henchmen? Are we going to close our eyes to revenge killings, public hangings, the kind of treatment Gaddafi's criminals have meted out for many a long year? I wonder. Libya is not Egypt. Again, Gaddafi is a fruitcake and, given his weird performance with his Green Book on the balcony of his bombed-out house, he probably does occasionally chew carpets as well.
Then there's the danger of things "going wrong" on our side, the bombs that hit civilians, the Nato aircraft which might be shot down or crash in Gaddafi territory, the sudden suspicion among the "rebels"/"Libyan people"/democracy protesters that the West, after all, has ulterior purposes in its aid. And there's one boring, universal rule about all this: the second you employ your weapons against another government, however righteously, the thing begins to unspool. After all, the same "rebels" who were expressing their fury at French indifference on Thursday morning were waving French flags in Benghazi on Thursday night. Long live America. Until...
...It is all wearingly familiar. And now we are back at it again, banging our desks in spiritual unity. We don't have many options, do we, unless we want to see another Srebrenica? But hold on. Didn't that happen long after we had imposed our "no-fly" zone over Bosnia?
This is a complicated mess and far from over.