I think a good example of what rom is talking about is here.

U.S. Army commanders and enlisted men who are patrolling east Baghdad, which is home to more than half the city's population and the front line of al-Sadr's campaign to drive rival Sunni Muslims from their homes and neighborhoods, said al-Sadr's militias had heavily infiltrated the Iraqi police and army units that they've trained and armed.

"Half of them are JAM. They'll wave at us during the day and shoot at us during the night," said 1st Lt. Dan Quinn, a platoon leader in the Army's 1st Infantry Division, using the initials of the militia's Arabic name, Jaish al Mahdi. "People (in America) think it's bad, but that we control the city. That's not the way it is. They control it, and they let us drive around. It's hostile territory."

The Bush administration's plan to secure Baghdad rests on a "surge" of some 17,000 more U.S. troops to the city, many of whom will operate from small bases throughout Baghdad. Those soldiers will work to improve Iraqi security units so that American forces can hand over control of the area and withdraw to the outskirts of the city.

The problem, many soldiers said, is that the approach has been tried before and resulted only in strengthening al-Sadr and his militia.

Amid recurring reports that al-Sadr is telling his militia leaders to stash their arms and, in some cases, leave their neighborhoods during the American push, U.S. soldiers worry that the latest plan could end up handing over those areas to units that are close to al-Sadr's militant Shiite group.

"All the Shiites have to do is tell everyone to lay low, wait for the Americans to leave, then when they leave you have a target list and within a day they'll kill every Sunni leader in the country. It'll be called the `Day of Death' or something like that," said 1st Lt. Alain Etienne, 34, of Brooklyn, N.Y. "They say, `Wait, and we will be victorious.' That's what they preach. And it will be their victory."

Quinn agreed.

"Honestly, within six months of us leaving, the way Iranian clerics run the country behind the scenes, it'll be the same way here with Sadr," said Quinn, 25, of Cleveland. "He already runs our side of the river."

...

Al-Sadr's success in infiltrating Iraqi security forces says much about the continued inability of American commanders in Iraq to counter the classic insurgent tactic of using popular support to trump superior military firepower. Lacking attack helicopters and other sophisticated weapons, al-Sadr's men have expanded their empire with borrowed trucks and free lunches for militiamen.

After U.S. units pounded al-Sadr's men in August 2004, the cleric apparently decided that instead of facing American tanks, he'd use the Americans' plans to build Iraqi security forces to rebuild his own militia.

So while Iraq's other main Shiite militia, the Badr Brigade, concentrated in 2005 on packing Iraqi intelligence bureaus with high-level officers who could coordinate sectarian assassinations, al-Sadr went after the rank and file.

His recruits began flooding into the Iraqi army and police, receiving training, uniforms and equipment either directly from the U.S. military or from the American-backed Iraqi Defense Ministry.

...

Etienne was on patrol one day when he saw Iraqi soldiers eating fresh vegetables and meat. The afternoon before, the same soldiers had complained that they had only scraps of food left. Who'd brought them their meal? It had come courtesy of Muqtada al-Sadr.

"Who's feeding the Iraqi army? Nobody. So JAM will come around and give them food and water," Etienne said. "We try to capture hearts and minds, well, JAM has done that. They're further along than us."

There's been ample evidence - despite claims to the contrary by American and Iraqi officials - that the death-squad activity isn't isolated to a few troops loyal to al-Sadr.

In the southeastern Baghdad neighborhood of Zafrainyah, an entire national police brigade was sent to be retrained last year- and much of its leadership was replaced - after its officers kidnapped 24 Sunnis, took them to a meat-processing plant and killed them.

Last month, four members of a neighborhood council in Etienne's sector - a mixed Sunni-Shiite area that abuts an al-Sadr stronghold - were leaving a meeting when national police trucks pulled up and men in Iraqi military uniforms piled out.

They grabbed the four men in broad daylight. One of the council members struggled. He was shot in the head and left to die on the street.

The remaining three were blindfolded and driven to a house. One of the four, a Shiite, listened as his two Sunni colleagues begged for their lives between beatings.

"They were pistol-whipping them and kicking them," Etienne said. "Finally, he heard the sound of a drill."

When the man's blindfold was taken off, he found that he was covered with the blood of his two friends, who were slumped over dead with drill holes in their heads.

"It was (al-Sadr's militia). They were trying to figure out who's who, and killing Sunnis," Etienne said. "They borrowed the vehicles from their friends in the Iraqi army and police who are Mahdi-affiliated."