In a darkened room the young American captain is discussing sewage improvements and militia infiltration with Iraqis on his Neighbourhood Advisory Council.

Suddenly an explosion rattles what is left of the windows, then another. A double car bombing at New Baghdad market five minutes away: 10 Iraqis dead, rising to 50.

“Another day in Baghdad,” mutters Staff Sergeant Bernell Parr. More than a week into the Baghdad security plan, viewed as maybe the last hope for the Iraqi capital — and the country — there are signs that the surge of US and Iraqi troops is having some effect.

Amid the poverty-stricken filth of Zafaraniya — a Shia suburb in southeast Baghdad — many Iraqis say that the visible increase in the US, Iraqi Army and police presence makes them feel safer and has eased the fear of rogue checkpoints and kidnap squads.

But two clouds still hang over the city. One is literal: the skyline scarred by columns of smoke rising from marketplace bombings and roadside mines. The other is the gnawing doubt about whether Iraq’s new security forces — hitherto crippled by desertion, corruption and extremist infiltration which caused previous similar plans to fail — will cope when the Americans leave.

The militias have gone quiet in recent weeks but noone — including US and Iraqi commanders — believes that Moqtada al-Sadr’s Mahdi Army has gone away. They have simply melted across the border into Iran, hoping that the surge will dissipate or evolve into a US exit strategy.

But in the joint US, army and police control rooms they focus on one overarching priority. “The mission is a stability mission,” insists Colonel Doug Heckman, senior adviser to the 9th Iraqi Army Division in east Baghdad. “A lot of bad guys are lying low. The difference between last time and this is stability. It’s going to be a lot more boots on the ground. And we are not going to leave. We know last time we petered out. We are not going to make that same mistake again.”

One boot on the ground — in ankle-deep, urine-scented mud, to be precise — is Captain David Eastburn, of 2nd Battalion 17th Field Artillery.

The 30-year-old from Colorado oversees the control room of a newly created Joint Security Station in Zafaraniya, where Iraqi police, army and US troops sit together beneath wall-size maps putting together joint patrols and quick reaction teams. Placing Iraqis from different branches of the security forces is deliberate — Sunnis who do not trust the Shia-dominated police can report suspicions to the army; Shias wary of the onceBaathist army can go to the police.

It is a busy week: the bombers strike twice near by, the second time as US and Iraqi soldiers kick a football around. At the scene there is early confusion. A fusillade leaves the Americans unsure if they are under attack from insurgents or if the police are — once again — firing wildly into the air. But order is quickly restored and the Iraqi security cordons, while not leak-proof, are effective. After 90 minutes the Americans withdraw, content. “Two years ago an incident like this, an [Improvised Explosive Device] on the street would have turned into a firefight between the Iraqi Police and Iraqi Army, either intentionally or by default,” said Staff Sergeant Eric Gillman, of the 240th Military Police Company. “Progress is irrefutable. The question is, is it long-lasting or is it temporary.” Noone is naive about the difficulties.

“We still have penetration of the Iraqi security forces by militias,” nods Captain Eastburn at the joint security station, an austere bunk bed and no-running-water operation in an old Iraqi police station. “It isn’t a mistake that we have established the JSS at police stations. In our area in Zafaraniya if you ask the people what the greatest source of militia infiltration is they will tell you the police.”

This is conceded even by the most senior Iraqi in east Baghdad, Major-General Abdullah Khames. Touring the charred New Baghdad market with US officers, he orders 6ft blast walls to be erected. Unafraid to face down the barracking of stallholders, he acknowledges the grumbles of Iraqis — and privately expressed incredulity of some front-line US troops — that the vulnerable markets were not blocked off to vehicles years ago.

On the ground Iraqi civilians, police and soldiers are divided between optimists and pessimists, but there is noticeably more support than for previous initiatives, many encouraged by the scale of the troop influx, hoping it will bring them safety for the first time in years. Hamid Abu Raad 30, a Sunni shop owner in Zafaraniyah, was encouraged that both Shia and Sunni militants were being rounded up: “I think this plan is a fair one because I saw the Iraqi and American forces have a list of the wanted men,” he told The Times. “They are running fair checkpoints, not like before. They treat the people nicely.”

Reflecting widespread nervousness about the Shia-led Government, he added: “I prefer the American forces to stay until the security problems are solved and achieve their task.”

But for the postAmerican era, noone is a prophet.

“I do see progress,” insists Colonel Heckman. “If we were going to be here for another five years I would be confident that things would turn around the right way. But we are not, so the uncertainty is right there.”

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