Syria's a terrible place to be at the moment. 80,000 dead so far, by the best estimates.

And Syria's air defences are a lot tougher than Libya's a few years ago. Libya is a large country with a small military. Everything is spread out, and easy to defeat. But Syria is a small nation with lots of air defences. A lot of old SA-2 and SA-3 systems, but some upgraded to make them resistant to jamming. They also have some modern systems like SA-17 and Pantsir-S1.

Maybe it's too strong for any nation to do anything.