The battleground is a section of Al-Quds Street, a garbage-strewn thoroughfare that separates the Jamilla and Tharwa neighborhoods from the northern heart of the Shi'ite enclave of 2.5 million people. The wall is intended to restrict access to the southern part of Al-Sadr City, from where militants launch rocket attacks on the International Zone.
"You go high, I'll go low -- on the count of three," a soldier from Charlie Company, 1st Battalion, 68th Armor Regiment, yelled to another on a recent afternoon.
The two were returning fire on snipers from al-Sadr's Al-Mahdi Army who were hiding in a nearby building and firing on troops constructing the barrier.
Moments later, the two let loose with long volleys of rifle fire at the top and the bottom of a building as other soldiers moved a new section of barrier into place.
Fighting a day later along the wall was so heavy that construction halted -- but only for a half-hour -- as soldiers poured rifle, machine-gun, and cannon fire on snipers firing from nearby alleyways and building.
The wall consists of 3.7-meter-high concrete slabs, each weighing over 5 tons. Soldiers from the 64th Brigade Support Battalion, a National Guard unit that normally transports water, fuel, and other supplies to soldiers, ferry the barriers using forklift loaders from a nearby staging area and lower them into place with a crane. Soldiers from 1/68 provide security and also help guide the slabs into place. The first slab was placed on April 19, and despite daily ambushes by gunmen, more than 1,000 now stand, meaning the wall is nearly half-completed.
"This is a mission that has to get done, to stop these thugs from firing their rockets and stuff," says First Sergeant Conrad Gonzales, of Charlie Company, 1st Battalion, 68th Armored Regiment. "Every day we get attacked, every day we're putting in barriers. The mission has to go on, it has to be accomplished and we can't let anyone stop us."
Southern Al-Sadr City's fields and other open areas put al-Sadr's militia and other fighters' rockets within firing range of the International (aka Green) Zone.
In late March and early April, militias did just that for days after al-Sadr called off a cease-fire with the Iraqi government and coalition forces after Prime Minister Nuri al-Maliki, a political rival, sent Iraqi soldiers into the southern port city of Al-Basrah to end violence by various Shi'ite gunmen, including members of the Al-Mahdi Army.
Some of the Iraqi forces in Al-Sadr City at the time retreated in the face of what one U.S. commander called "concerted and coordinated" attacks by extremist cells, but new units later took their place as U.S. forces entered the fray. The end result is that U.S. troops, once confined to the outskirts of southern Al-Sadr City, are now present in the enclave itself, operating -- independently and jointly with Iraqi forces -- out of special outposts
Disrupted Daily Life
U.S. officials say the barrier will help block militants from moving their weapons into the area through the many side streets that cross Al-Quds Street. Residents of both northern and southern Al-Sadr City can still cross from one district to the other, but they will have to do so through just three main crossings where Iraqi Army troops check vehicles for weapons and other contraband.
Smoke from a grenade helps obscure a soldier removing hooks from a crane (RFE/RL)
"They [the residents of southern Al-Sadr City] are not ecstatic about it," says Captain Todd Looney, commander of 1/68's Charlie Company. "Unfortunately you can't make a barrier or an obstacle that only obstructs the movement of the insurgents; unfortunately, it's going to disrupt the movement of some civilians because the…[militants] hide among them.
"Even though they are inconvenienced in their daily movements around the city, I think they understand. They may not appreciate it, they may not be happy about it, but I think they understand."
According to company statistics, 118 Shi'ite gunmen were confirmed as killed in wall battles between April 19 and May 2. Two U.S. soldiers were wounded -- one shot in the side, another hit in the chest by a piece of shrapnel from a rocket-propelled grenade (RPG).
Eight improvised explosive devices have gone off along the unbuilt wall route during the same period, while 48 others were detected. Seventy percent of attacks on soldiers providing security for construction of the wall come from the north side of Al-Quds Street. The fiercest battles occurred on April 27, when bands of gunmen attacked during a blinding dust storm.
Al-Sadr, believed to be in Iran at present, has vehemently denounced the wall and likened it to the barrier Israel has erected along the West Bank.
Al-Quds Street is a virtual no-man's land at the moment. Shops along its northern side are either partially destroyed or boarded up. Among them is "Bazza of Truthful, the Honest Assemble" appliance store. All bear the marks of bullets. Insurgents creep into them, usually under the cover of darkness, and then wait in their windowed recesses to later fire on U.S. troops.
On the south side of Al-Quds Street are many abandoned homes. An occasional resident seeks entry by slowly walking to them from side streets, hands up in the air to show soldiers they are no danger.
Generally they are allowed to pass as long as they are at a safe distance, but soldiers have learned not to be complacent. Last weekend, a man with an innocuous-looking plastic shopping bag was shooed off with a warning shot as he passed too close to men of Blue Squad, 1/68. He dropped his bag when he left and soldiers later decided to probe it with gunfire. The bag erupted into flame and soon bullets concealed in it began to explode.