Two Syrian kids, hold a Syrian flag with a poster of Bashar al-Assad during a pro-Assad demonstration, in Damascus, March 25, 2011. (Hussein Malla/Associated Press)

Margaret C. from Albany, NY writes in with this question on Syria and a potential successor to Syrian President Bashar al-Assad:

How can the Obama administration be keen on Syrian President Assad stepping down when they have not once mentioned who would take over? Nearly a year after the massacres and we still have no idea who would follow Assad? How is that possible? Is the intelligence community doing their job in determining who the players are? And if they are, does John McCain not know about it? He hasn’t offered up an alternative to Assad either.

The answer comes from Bruce Riedel, a Brookings Institution senior fellow who spent 30 years in the CIA focusing, in part, on the Middle East:

The situation in Syria is extremely volatile. The conflict is becoming a sectarian civil war between the ruling Alawite minority that controls the army and the Sunni majority. No one knows when Bashar al-Assad will leave power or how he will be removed. Assad probably believes he can hold on to power just as his father did when he was confronted with a massive urban revolt in Hama in February 1982. Hafez Assad shelled the city into submission killing perhaps 20,000 people. Bashar’s Russian and Iranian allies probably believe he can suppress the current unrest by force as well. If they are wrong, a number of scenarios are possible.

If the army splits apart then a Sunni general is likely to emerge as the next leader of Syria which has been ruled by military dictators since 1948. So far the army has remained relatively united behind Bashar with only low level defections. No senior general has yet to go over to the opposition and bring his unit with him but it could yet happen as it did in Yemen.

If the opposition does prevail over Assad and ousts him by mounting violence, it will likely be dominated by the Muslim Brotherhood, the most cohesive and organized party in the opposition. It has led the struggle against the Assads since before Hama. The Syrian Muslim Brotherhood is more extreme than its counterpart in Egypt. It might allow the Syrian exiles who form the Syrian National Council to have the trappings of power, but the Brotherhood will have the reality.

A palace coup is also possible. One of Assad’s lieutenants may decide to do him in and then try to make a deal with the opposition. This could start to unravel the whole regime, however, and lead to chaos.

Another scenario may see the country split into warring regions much as Lebanon collapsed into sectarian blocs in the 1970s. The Alawite community knows that it has nurtured deep hatred and animosity among many Sunnis for decades and that the current violence is only adding to the spirit of Sunni revenge. Most Alawis believe their future is now tied to the Assad family so they will be prepared to fight together for fear of hanging separately.

The Arab League and the U.N. would like to avoid these violent scenarios by coaching Assad to leave voluntarily and hand power over to an interim figure, probably Vice President Shara. This is what has happened in Yemen. But there is no sign that Bashar will play along.

The one constant in these scenarios of change is that Iran will be a loser if Assad goes. A Sunni general, state collapse or a Muslim Brotherhood regime would all mean Iran will lose its most important ally in the Middle East.

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