Despite all the talk of Assad winning lately, this doesn't sound a whole lot like winning:
The black flag of jihad flies over much of northern Syria. In the center of the country, pro-government militias and Hezbollah fighters battle those who threaten their communities. In the northeast, the Kurds have effectively carved out an autonomous zone.
After more than two years of conflict, Syria is breaking up. A constellation of armed groups battling to advance their own agendas are effectively creating the outlines of separate armed fiefs. As the war expands in scope and brutality, its biggest casualty appears to be the integrity of the Syrian state.
I'd add at least two more developing entities: a more acceptable rebel faction in the south being set up by Jordan with American backing and an eastern faction that draws support from Anbar province's Iraqi Sunni Arabs.
I suspect that Assad won't be able to hold Damascus unless an international deal saves him before his new militias are burned up in combat. At that point the faction that we are working on in the south might have the best shot at dominating the capital region.
I think that the potential disruptions of a catastrophic fall of the Syrian state means that it might be better to save Assad as a local prime minister in a weak federal state. If that can marginalize the jihadis of the north and get a quieter environment to collect and destroy chemical weapons assets, this might be the way to go.
As long as we don't forget that the total defeat of Assad is the ultimate goal even after accepting a post-Syria Assad regime.
The choice between these alternatives isn't clear to me. But I would like the administration to try to defeat Assad, so either path is likely superior to following from behind and hoping for the best. Failing to harm an enemy is a foreign policy sin, as far as I'm concerned. I'm certainly not calling for open intervention--not even air power, although that would not have to be a first step to ground escalation (see Libya)--but we should use available levers of power to push events in ways best (or least bad) for America.