Vigeant's frustration was symbolic of the dilemma facing the U.S. military as it tries to quell violence in Sadr City without further inflaming Sadr loyalists, who want to drive the United States out of Iraq.
Most comparisons to Hezbollah go only so far, though, and many Sadrist officials point out the obvious: Just as Hezbollah was impossible without Israel's 1982 invasion of Lebanon, so is Mr. Sadr's movement without the assassination of his father on Mr. Hussein's orders in 1999 and the American invasion and occupation four years later.
"Jaafari could not have been elected without Sadr's support". In one sense, his participation represents the realization of a central American goal: to bring populist, violent figures -- whether Sunni or Shiite -- off the battlefield and into democratic politics.
Indeed, Mr Maliki would not have kept his post as prime minister after last year's inconclusive election without Mr Sadr's endorsement.
Senior Shiite officials said in interviews that the militiamen, acting without Mr. Sadr's approval, wanted to trade Mr. Carroll for a Mahdi Army commander imprisoned by the British in Basra.
Mr. Maliki's move against Mr. Sadr in Basra, done without even consulting Iraq's "democratically elected" Parliament, was an attempt to take out his opponent by force rather than wait for the October provincial elections.
The American strategy is to contain the anti-U.S. violence spawned by Sadr's young Shiite followers without alienating the larger Shiite community.
Those rogue elements, they say, carry out attacks without guidance from Mr. Sadr or his top commanders.
Without an order from Mr. Sadr for these remaining fighters to leave, one American official said, "There will be a fight".
But the agreement was seen as a way for the Iraqi government to assert control over the Sadr City areas north of the wall without ordering Iraqi troops to fight their way in.
