The smoke of battle between US forces and the army of poor young Iraqis supporting anti-American cleric Moqtada al-Sadr now rises over Baghdad.
Less than two weeks after an agreement ended a costly confrontation in the southern city of Najaf, the US is again fighting the followers of the fiery religious leader who rails against the "American occupation."
Only now the fighting is in the sprawling, densely populated slum that is Mr. Sadr's base of support. That this fight is in Sadr City and not Najaf, is both good and bad for the US, analysts say. Confronting Sadr's loyalists here removes the complication of fighting in one of the holiest sites of Shiite Islam. But it also means the Americans are fighting on the enemy's turf and in the even bigger showcase of Baghdad.
"It's a Hobson's choice. It takes away the symbolism that somehow we're fighting Islam," says Ellen Laipson, an intelligence specialist and president of the Henry L. Stimson Center in Washington. "But if the US objective is to demonstrate that we're on an upward trajectory, that's hardly served by having deadly fighting in the capital - where the US has its strongest presence - and where the Allawi government [of Interim Prime Minister Iyad Allawi] already faces assassination attempts and other challenges."
The accord that broke the standoff in Najaf left the hard realities of opposing political viewpoints to be confronted another day, analysts say.
That "other day" is being tested in Sadr City - named after Sadr's revered late father.
On a trash-piled street deep within the maze of this crumbling neighborhood of several million people, a horse lies dead outside the pockmarked house where neighbors say American planes shot repeatedly early Wednesday morning.
The shooting added four more to Sadr City's official death toll of 40 residents since Tuesday, the neighbors claim. They insist attempts to remove the wounded by car were met by more gunfire.
"The Americans are killing our fathers and brothers just as Saddam did, so of course the boys will join the resistance!" wails Bushra Hamood, a black-robed woman who says she lost neighbors in Wednesday's air attack. "I thought the Americans could do a lot of good in Iraq, but it has come to this!" she cries, pointing to the blasted house and the putrid waters oozing down the street. "We have been pushed back to the age of boiling water."
What began Monday as rumors of imminent clashes turned to deadly cat-and-mouse fights on Tuesday and Wednesday.
US officials say they entered the slum, where fetid open sewers run on many streets, led by tips of weapons caches and bomb factories. The night raids were answered by varying levels of attack from Sadr's militia. A US Marine was also killed Tuesday when his tank was hit by a rocket-propelled grenade. A second US soldier patrolling Sadr City streets early Wednesday morning became the 1,000th US military death in Iraq.
Sporadic fighting continued in Sadr City Wednesday, with US officials saying they would not back off from patrolling. In Fallujah, American jets struck a suspected militant stronghold used to plan attacks on American forces, the US military said.
Thick black smoke rose over Sadr City Wednesday as an assistant to Sadr, Sheikh Mohammed Ali Khadeem, sipped tea in his home and predicted the "occupation" foretold more violence.
"This war inside Sadr City and indeed all of Iraq will never end until the last American soldier leaves," he says, his two-year-old son Ali asleep in his lap. Arrayed around him are smiling young men from Sadr's Mahdi Army, most holding a Kalashnikov in one hand as they, too, sip tea, with the other.
Mr. Khadeem, who is also a fighter in the Mahdi Army - one of several militias the Allawi government says it wants to disband - says his fellow fighters had respected a week-old cease-fire, which Sadr had called to allow him time to formulate a political platform. Elections are planned for January. But Sadr's negotiations with the Allawi government have stalled. It was the Americans, he claims, who "provoked" the violence by running raids into the neighborhood beginning Monday night.
"Despite what they say, the Americans cannot accept the idea of [our] participation in any Iraqi government," he says, Sadr posters dotting the whitewashed walls around him. "It would be a government of Islam that the Iraqi people want, but not one the occupiers want."
A tall, thin man dressed in the traditional long white dishdasha, Khadeem reserves his severest words for Prime Minister Allawi - "a tool of the Americans," "a CIA thug," referring to Allawi's long relationship with American intelligence - suggesting any definitive accord with the government will be difficult.
It is not only Sadr supporters who say finding a political solution to the Sadr challenge will be arduous.
"The reality is that Sadr and many who support him fundamentally reject the US occupation and the legitimacy of any Iraqi government that is not based on their concept of Islamic goals," says Anthony Cordesman, an Iraq expert at the Center for Strategic and International Studies in Washington.
"There will be cycles of violence and cease-fires as long as Sadr is around unless he feels he can somehow win an electoral victory," he says. But "the idea he will compromise or evolve toward a peaceful set of relations with the US or even the interim Iraqi government is simply not realistic."
Yet as stark as the challenge seems, the fact Sadr is a recognized leader - even if a troublesome one - with a sizable following may make Sadr City less grim to deal with than other, more extremist strongholds, some Iraqi officials believe.
Central Iraqi cities such as Fallujah and Ramadi, where Sunni extremists have taken over, offer fewer if any negotiating options because they are held by groups who accept only two options: either what Iraqis increasingly call "Talibanism," or martyrdom.
Even though one hears more and more talk of martyrdom among Sadr City's Mahdi fighters, Iraqis are betting the majority of the district's population want political power here on earth - and that Sadr understands that.