Excellent commentary from Philip Gourevitch in The New Yorker. The broader context:
There is a risk of a regional Sunni-Shiite conflagration, as Saudi Arabia, which backed Bahrain’s crackdown on Shiite protesters, has advocated arming Syria’s opposition. There are Turkish misgivings about Kurdish rebels establishing bases in Syria; and Israeli anxieties about Assad’s accelerating military assistance to Hezbollah forces. There is also the question of Syria’s enormous chemical-weapons stockpiles: might Assad use them? Can they be secured if he falls?
And the awkward truth:
Mikhail Margelov, speaking for Prime Minister Dmitry Medvedev, said, “One cannot avoid a question: if Assad goes, who will replace him?” The hawks have no answer, nor, for that matter, does anybody else, including the main opposition group, the Syrian National Council, a coalition of seven infighting factions—ranging from Christians to Kurds to the Muslim Brotherhood—composed almost entirely of exiles, whose only consistent demand is for international military intervention.