Sadr leads the Shi'a Mahdi Army. It's arguably the biggest and most powerful insurgent group, and Sadr is a charismatic figure widely-respected amongst Shi'ite Muslims in Iraq (who make up about 60-65% of the Iraqi populace).
In 2006 and early 2007, Sadr and his followers were on the rise, gaining ground and expanding operations. But with this expansion came control problems -- corruption in the lower echelons, in-fighting and splinter groups, unsanctioned violence. That was about when we were hearing horror stories of death squads in the streets, and rates of violence in Iraq were high.
The U.S. surge made the internal divisions amongst the Shi'ites worse. So in order to regain control, Sadr announced a six-month freeze on all Mahdi Army activities, starting in August of 2007. This ceasefire has mostly held and, together with increased U.S. and Iraqi military presence in Baghdad, helps account for the dramatic drop in violence. But how long can we expect that to last?
Today, many are breathing a sigh of relief as Sadr announced a 6-month extension of the ceasefire. But that doesn't mean we'll have smooth sailing from here on in. According to an excellent report from the International Crisis Group (ICG), "the situation remains highly fragile and potentially reversible. If the U.S. and others seek to press their advantage and deal the Sadrists a mortal blow, these gains are likely to be squandered, with Iraq experiencing yet another explosion of violence."
Instead, the ICG recommends that the U.S. and Iraqi forces work on incorporating Sadr and his followers into the political process. They suggest narrowly circumscribing operations against the Mahdi Army and Sadrist movement by:
(a) focusing on legitimate military targets, including armed groups involved in attacks against civilians or U.S. or Iraqi forces, weapon stockpiles and hideouts, or arms smuggling networks;The ICG also urges freezing recruitment into the Shi'ite sahwa (awakening), the U.S.-backed tribe- and citizen-based militia set up to fight the Mahdi Army. Instead, we should concentrate on building a professional, non-partisan security force, integrating vetted Mahdi Army fighters.
(b) taking action against Sadrist-manned patrols or checkpoints; and
(c) tolerating Sadrist activities that are strictly non-military, including those involving education, media, health services and religious affairs.
So you see, whether or not gains attributed to the surge can be maintained depends on how smart our forces play it with Muqtada al-Sadr. In fact, a lot of the gains themselves might be more accurately attributed to Sadr's ceasefire. It's not a simple question of the number of troops, but rather a complex intersection of factionalized local politics, religious and sectarian divides, and fragile cooperation.