[pemulis]

I see where you're coming from, but there are a number of things that would need to happen for this to work.

1) The Assad family would have to find the threat from NATO credible. 2) They would have to believe that there is no chance of defeating the rebels militarily and outlasting NATO bombardment. 3) The major power players in the Assad government would have to be willing to accept life in exile, with no opportunity for travel or engagement with the rest of the world. (Even Ben Ali, the dictator who left Tunisia semi-voluntarily, has an international warrant out for his arrest.) 4) Some country (presumably America) would have to be willing to either pay them a significant lump sum out of their own pocket or allow them to loot Syria before they leave.

You could pick any one of these apart.