The town officially goes by the name of Shughart Gordon - a cluster of buildings set in forests that could be almost anywhere in the world. But in the minds of the soldiers of the 101st Airborne who stormed it, it was Baghdad.

Troops from the division's 3rd Brigade fought from house to house in this mock-up settlement, as part of an exercise intended to get them ready for their next battle, only a few months after their return from Afghanistan.

Most of the 600 soldiers in the exercise believe that if an invasion of Iraq is ordered, the highly mobile 101st Airborne, the "screaming eagles", will be among the first units sent in. And they are aware that the endgame against Saddam Hussein's special republican guard is likely to be fought out in Baghdad, in Tikrit - the Iraqi dictator's home town - and other urban areas. They would be full of civilians, snipers and booby traps.

Perhaps that is why the planners of the war game chose the name Shugart Gordon for the fictional Baghdad. Urban warfare has given US military planners bad dreams since the assault on the Somali capital Mogadishu in 1993, when two Black Hawk helicopters were shot down and 18 American soldiers were killed in the labyrinth of the capital.

Shughart Gordon is named after two of those dead soldiers.

Along with a chemical or biological attack, urban warfare is the US army's biggest nightmare.

That goes for Private First Class Mark Meshreky too. "Urban warfare is the number one worry," Private Meshreky said. "You've got to have 360-degree vision. In Afghanistan, around Kandahar it was just a desert. You could see in every direction. Here, you've got to see around every corner."

Even through the camouflage paint on his face, it was clear that Private Meshreky was exhausted. He had not slept for more than 30 hours, but as the sun came up over Shughart Gordon, he beamed with the elation of a survivor, as dozens of fellow soldiers lay dead and wounded.

On this occasion, they had been hit by lasers fitted to the guns of the town's defenders, played with appropriate ferocity by two platoons from the 509th Parachute Regiment. The lasers are picked up by shiny black receptors on every uniform and helmet, that emit a whine when struck. Explosions are mimicked with ear-bursting effect by Hollywood-style pyrotechnics.

It is as close to real life as the army can make it. And these exercises, no matter how well orchestrated, can also be dangerous. Two soldiers were killed in a similar exercise last week when a tank ran over them. But much of the adrenalin in this particular war game was the knowledge that it could soon be played out for real in Iraq.

"It's kind of why we're doing this," said Lieutenant Colonel Anthony Sabb, who led the 15 Black Hawk helicopters used in the assault. "It's never away from our minds that the things we are doing here are going to happen to us in real life.

"We want to avoid an urban fight as much as possible. You have the danger of fratricide [killing soldiers on your own side]. And we don't want to hurt civilians.

"We'll be at a disadvantage out there because there's a lack of knowledge of what we're about. The regime's propaganda machine is at work. People of Iraq don't know we're not there to hurt them."

Lt Col Sabb's other big worry was in a satchel at his waist - his chemical and biological protection gear. While waiting for the war game assault, the helicopter squadron was attacked three times with chemical weapons.

In the final assault on Shughart Gordon, some of the 3rd Brigade's troops had to don protective gear to detonate what they thought could be a chemical booby trap. In the town's last stand, however, the defending forces opted not to use chemical or biological agents, on the grounds that it would be suicidal - a premise that might not hold in Iraq.

The demand for the war game facilities at Fort Polk is at an all-time high. The training base is normally dormant in December, but not this year. Next week, it is the turn of the 10th Mountain Division, another combat unit that fought in Afghanistan and could well play a role in Iraq.

The Louisiana base is a prime example of everything the US army is good at. It is a technological marvel which allows officers to watch the progress of the battle through hundreds of thermal imaging cameras and, through satellite positioning technology, to see individual platoons move across maps lit up on giant screens in a control center.

In the cold night outside, however, the vastly superior American technology was of less use in close-quarters street fighting. A mighty MI Abrams tank was brought to a halt for more than an hour because barbed wire got tangled in its tracks. Dozens of troops were picked out by a single sniper before he could be found and killed with a tank shell. Total casualties from the exercise were not released.

It is clear from the hints seeping out of the Iraqi regime, that in the event of a US attack, President Saddam would not repeat the mistake he made 11 years ago of leaving his best troops out in the desert to be slaughtered by American air power. This time, he is more likely to pull back the special republican guard into Baghdad and Tikrit where civilians would serve as human shields.

The US military is trying to send a message, to say it is not afraid of going into the streets, which may in part explain why international journalists, including a television crew from the Arabic channel al-Jazeera, were invited to Fort Polk.

"If you show you're ready and willing to go in there and do it, then perhaps the Iraqis will think twice about it," said Gary Anderson, a retired marine colonel who is advising the Pentagon. "I think we have to show we won't be deterred by this kind of blackmail, or else we'd turn urban warfare into a bogey man, and we'll be held hostage by it."

© Guardian Newspapers Limited 2002

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