Will the UN intervention in Libya stop Qaddafi?

Update: Obviously this would need to be significantly updated in light of today's assault on Benghazi. It sounds like Qaddafi's forces have simply swung around Ajdabiya -- the rebels' lack of mobility means that he can do that -- and thrown what he has against the east's capital. It seems a pretty desperate gamble, given that Benghazi should be extraordinarily hard to subdue, and may be intended to create a situation where intervening powers will be forced to strike before they are ready, which significantly raises the risk of major civilian casualties . He may even be hoping that they will be tempted to insert ground troops. Maybe like Saddam, he is already thinking ahead to a post-regime collapse scenario, and wants to make the situation as messy as possible before he goes.

I can only imagine the elation in Benghazi last night. Earlier this week I paid an extremely brief visit to eastern Libya, and watched morale see-saw back and forth according to the latest rumors from the battlefield. It looked like Qaddafi would just grind forward all the way to Benghazi, and almost everyone to whom I spoke was desperate for a no-fly zone (some also rejected "foreign intervention" at the same time, but appeared to associate the latter phrase with ground troops). As it seemed increasingly unlikely that anyone would intervene, there was a growing sense of abandonment. People would start to clutch at straws -- any rebel announcement of a miraculous turnabout success, however unlikely it sounded, was greeted by joyful cries of Allahu Akbar and the discharge of firearms into the air. But now we may have a genuine tide-turning event, real deliverance from on high. I could see the crowds cheering on al-Jazeera, but I'm sure that it conveyed only a small part of the ecstatic sense of relief which Benghazi residents are now experiencing.
So -- is their elation justified? Is this just going to be another one of those bitter early Bosnia or Iraq experiences, where international intervention is either ineffective or maybe even makes things worse? Did last night's UN Security Council resolution come too late?
I suspect not -- that the Libya resolution will very likely save the cities of the east, and will probably eventually bring down the Qaddafi regime. But there may be some bloody days ahead.
Firstly, in terms of sheer firepower, aircraft are not Qaddafi's deadliest military asset. That dubious honor probably goes to his tanks and rocket artillery. But these are probably now legal targets for UN aircraft thanks to the clause in the Security Council resolution authorizing "any necessary measures" to protect civilians. A no-fly zone is also extremely important psychologically. Rebels were terrified of attacks from the air, particularly when moving on the open highways, and airpower probably contributed greatly to Qaddafi's ability to outflank and isolate rebellious towns. For loyalist forces, meanwhile, having the skies turn from friendly to enemy might be deeply demoralizing. Rebels in Benghazi also say that the no-fly zone means that UN electronic warfare aircraft are going to start jamming loyalist communications. I don't know if this is true, but it would pretty quickly bring home to the regime that the balance of power on the battlefield is going to be very, very different.
There seem to be two main fronts in the war right now -- one around Ajdabiya, the gateway to Benghazi and the east, and one around Misrata, Libya's third-largest city, with over half a million people. From a humanitarian standpoint, the situation around Misrata is much more critical. The city has been under siege for weeks, and power and water have been cut off. Pro-rebel websites are reporting via phone conversations with residents that Qaddafi forces are attacking the city, despite having declared a ceasefire. The regime may be trying to grab Misrata as quickly as it can and make its control of western Libya a fait accompli.
Rebel-held towns have in the past proven very difficult for the regime's armed forces to subdue, so Misrata may be able to hold out for days or even weeks. However, resistance in towns has also collapsed without much warning, so Misrata might be on the verge of falling. Either way, the civilian population is probably suffering very badly. This would be a situation in which the UN coalition would want to invoke the "all necessary measures" bit -- . While it's my understanding that it's fairly easy to spot and destroy tanks and artillery in the open desert, destroying vehicles in built-up environments would usually require going in low with close support aircraft, and that would be something that most air forces would be loathe to do without first spending a week softening up Qaddafi's anti-air defenses. Drones may be an alternative which limits the risk of losing pilots, but drones are still valuable hardware, and aren't exactly optimized for flying through a hail of ground fire. One hopes that the mere imposition of the no-fly zone might be enough to sufficiently stiffen rebel resolve and demoralize regime forces to prevent a Srebrenica in Misrata, but one can't count on that.
The other front is Ajdabiya, a desert town which is a gateway to the highways of the east and to Benghazi. Ajdabiya has been under attack for several days, and its fall has been reported a number of times. Qaddafi's main military asset here is his airpower and what appears to be rocket artillery massed in the surrounding desert, both of which would presumably be quite vulnerable to UN aircraft. Ajdabiya is also not isolated like Misrata, so most civilians who are not staying to defend their homes have probably already fled. If Qaddafi takes Ajdabiya in the next few days, as the no-fly zone is being set up, it wouldn't be pleasant -- SUV-loads of regime loyalists could roam the highways of the east, disrupting Egypt-Benghazi food convoys and generally causing panic -- but it would not quite equal the disaster of Misrata's fall. At this point, I doubt the regime would be able to push on to Benghazi or other eastern cities, particularly as the UN builds up its capacity to attack Qaddafi ground forces.
That would be my guess about the immediate impact of the resolution. I'll try to blog something about the chances that the rebels can now start to roll the regime back, the danger of political backlash, etc.