On a hot, gray and dusty morning, Lt. Col. Gary Volesky's heavily armored patrol rumbled slowly past the remnants of a building his forces had destroyed only two nights before. A crowd of youths was working to rebuild it, cinder block by cinder block.

Volesky ordered his five Bradley Fighting Vehicles, with long guns and missiles mounted on top, to take a left rather than wade into a crowd that began to move excitedly across the roadway and its rudimentary barriers.

"We don't want to create a scene," Volesky told his gunners. "We'll see what the boss says about it."

By boss, he meant Col. Robert Abrams, the commander of U.S. forces in the Sadr City area, who had ordered the destruction of the building, which housed an office of Shiite Muslim cleric Moqtada Sadr.

Sadr City, the Baghdad front in Sadr's rebellion against the presence of U.S.-led occupation forces, was largely quiet Tuesday, two days after fighting there killed 34 insurgents. The masked gunmen who blocked streets, shut down commerce and drove police officers and civil administration workers out of their offices on Sunday had all but withdrawn from Sadr City's smelly, trash-filled alleys.

On Tuesday, the neighborhood presented a confusing panorama, making it unclear who among the impoverished throng was friend or foe. Residents interviewed later generally blamed the violence on Sadr, a 30-year-old militia leader and the son of the assassinated cleric for whom Sadr City is named.

But the Americans were taking no chances.

They moved through the huge slum only in the Bradleys, which are impervious to rocket-propelled grenades, the rebels' heaviest weapon. The more vulnerable Humvees and foot patrols did not take to the streets. American municipal chores in Sadr City that had been delayed for a month -- fixing sewers, clearing trash, providing jobs -- have been postponed indefinitely.

Keeping order in Sadr City is an important objective for the U.S. and allied commanders in Iraq, authorities here say.

The neighborhood contains one-third of Baghdad's 5.5 million people, but violence in Sadr City on Sunday rattled the nerves of the entire capital. And beyond Baghdad, Sadr's revolt has encompassed a half-dozen Shiite cities, complicating efforts to pacify a country troubled by a year-long Sunni Muslim insurgency.

Tuesday's Bradley Fighting Vehicle tour of Sadr City highlighted the lingering concerns of U.S. troops. Besides the violence, a year of futile efforts to improve conditions in Sadr City has fed hostility, said Volesky, the tall and lean battalion commander in charge of combat operations in the neighborhood.

"We've got to transit as fast as we can to improving the quality of life," he said.

From the metallic insides of an M2 Bradley, the outside world is viewed through a television screen. The images are either old-style black and white or greenish from a device that picks up heat emissions. An otherwise invisible figure in a dark doorway appeared as a ghostly haze.

There was a busy market, rows of open storefronts, piles of tires and scrap metal, wandering shoppers and unsupervised children. Sheep, mules and horses walked past on carpets of garbage. Most of the bystanders watched impassively. Some scowled. A few offered friendly thumbs-up. Police stations were once again populated by U.S.-trained officers.

At one point, a group of schoolboys began to gleefully toss stones at the thunderous Bradleys.

"Here's a great place to win some hearts and minds," Volesky said.

Then, suddenly, he ordered: "Watch the alley. I got a lot of people running around. That's not a good sign. . . . We heard there were some issues around Fox," the code name for a broad street they were approaching.

"We made contact just south of Copper," answered a driver, referring to an incident on another street the other day.

The crew noted a burned-out car with a propane tank sticking out of it. "Circle that location, in case we get indications they are planting IEDs," Volesky said.

IED means improvised explosive device -- a roadside bomb. "We hit a lot of IEDs two nights ago," Volesky continued. "One went off right in front of the driver. It wrapped up the turret in wire."

The Bradleys waded into pools of raw sewage. A putrid smell filtered inside. Passengers earned the unforgettable opportunity to breathe in Sadr City.

Volesky offered an explanatory tale of futility.

The occupation authority supplied 70 trash trucks and numerous dumpsters last year to institute garbage collection, he said. Iraqi contractors took the trucks, then illegally charged people for pickups that were supposed to be free. In the meantime, the contractors used them elsewhere in the city for other lucrative chores.

People wouldn't pay the fee, so trash built up and clogged the already inadequate sewer lines, Volesky continued. Other Iraqis who had contracted to suck the debris from the sewer lines also tried to shake down residents. The sewers were oozing black crud onto the streets. Looters seized the dumpsters and used them for scrap metal.

When Sadr City settles down, U.S. commanders hope to launch Operation Iron Broom, in which soldiers will help clean up the mess, Volesky said, explaining: "We got to give them a little love."

The tour ended with a race down a largely empty stretch of road where bombs have often been planted. Volesky reminded a subordinate to get in touch with an Iraqi policeman to erase Sadr portraits that were stenciled on the police station wall.

In the afternoon, a few white-masked youths patrolled near the site of Sadr's leveled office, but elsewhere in the neighborhood the only visible sign of potential problems was the presence of small boys holding gasoline bombs made of soda pop bottles.

Residents were generally unwilling to be interviewed. Those who agreed to speak expressed disgust over the confrontations, which they blamed on Sadr's militia.

"These are a bunch of guys who can't do anything against the Bradleys and tanks. They will only damage us, maybe get us killed. But we are afraid to say that in front of them," said Mahdi Hasan, a shop owner.

"I don't know what these Sadr people want," said Ali Maki, an unemployed army veteran. "And we don't think this cleric has any chance to make a government here or in Iraq. Iraq is not a little mosque on a dirty street. Look at them rebuild the office. Why don't they put the labor into rebuilding the country?"

One man working to repair Sadr's building said he was "doing it for God."

"If the Americans come to destroy it, we will build it again and again," said Saad Lawi, who was applying the finishing touches of whitewash.

Lt. Col. Gary Volesky of the Army's 1st Cavalry Division patrols Baghdad's Sadr City neighborhood in his Bradley Fighting Vehicle. A gunman stands guard in Sadr City after U.S. forces destroyed an office of Shiite cleric Moqtada Sadr there in fighting early Monday.Sadr City residents start to rebuild the structure that Sadr's militiamen had used as a district headquarters in the capital.