Updated

Just two days before a mission to send hundreds of Iraqi soldiers after insurgents in this troubled western part of Iraq, U.S. and Iraqi commanders confronted an untimely problem — an Iraqi battalion commander was suddenly fired for incompetence.

The commander's soldiers, a third of those assigned to the mission, would be absent for an operation designed in part to introduce the unit to residents in this town between the troubled cities of Ramadi and Fallujah, about 50 miles west of Baghdad.

The missing battalion underscored what U.S. commanders call the Iraqi army's most glaring weakness in this restive part of the country: a shortage of soldiers able to take on their own "battle space," or areas where they are primarily responsible for security.

The lack of Iraqi troops has complicated not only the operation in Bidimnah early Sunday, but also the broader mission here in Anbar province.

American commanders said an entire Iraqi brigade, about 2,500 troops, has taken over parts of the nearby city of Khaldiyah and an adjacent agrarian area from U.S. troops. But U.S. military advisers who mentor the Iraqi unit said just over half those assigned Iraqi soldiers were actually present.

The Iraqi brigade already was short several hundred soldiers before they deployed to Anbar province from the northern city of Mosul, the advisers said, and about 500 more deserted when they arrived in late August and faced their first insurgent attacks.

"The most significant problem facing this brigade is personnel shortage," said Marine Col. Daniel Newell, head of a squad of about three dozen military advisers, called a Military Transition Team, attached to the 3rd Brigade of the 1st Iraqi Division.

Moreover, an Iraqi army policy giving soldiers 10 days of leave each month means even fewer soldiers are available. Fewer than 1,000 Iraqi troops are consistently stationed in this area if the soldiers on leave are deducted — so this brigade was in reality about a third of its size on paper.

"A lot of them, when they were told they were coming to Jazeera and Habaniyah, they quit," said Marine Staff Sgt. Juan Santiago of New York City, speaking of two towns just outside Bidimnah. Santiago saw more than half his trainees quit the Iraqi army over the fall.

The number of Iraqis in the brigade has stabilized over the past two months as increased patrols have helped control the violence, Santiago said, but "it's always possible that more will quit."

The problems with the brigade hint at the obstacles that loom for U.S. commanders eager to cut American troop obligations in Iraq. A full withdrawal of U.S. forces would require Iraqi forces to take over large swaths of violent Anbar province, but so far only a handful of Iraqi forces have done so in relatively small areas.

"The case where you'll see less coalition forces here than now, that'll probably be in 2007," said Col. John L. Gronski, who commands the 2nd Brigade Combat Team, 28th Infantry Division that oversees the swath of land from Ramadi to this farming area along the Euphrates River.

Despite the desertions, U.S. commanders point to the success of those Iraqi soldiers patrolling with minimal or no U.S. assistance. On Sunday, two days after the Iraqi battalion commander was dismissed, Iraqi soldiers fought in gunbattles and discovered weapons caches during the mission dubbed "Operation Final Strike."

"The Iraqi soldiers have to be good enough to beat their opponent, and their opponent is not that good. And they outnumber their opponent — that's the good news," Newell said.

But other fundamental problems persist in the new army. Two Iraqi soldiers were wounded during Sunday's operation by their own friendly fire.

And, during a handful of gunbattles with insurgents last year, Iraqi soldiers simply dropped their weapons and walked away while U.S. Marine advisers continued fighting back, Newell said. In other cases, though, Iraqi soldiers jumped in front of U.S. troops to protect them, he added.

The Iraqi soldiers in Anbar, like most in the country, also suffer from severe shortages in armored vehicles. Most soldiers drive around in civilian trucks with improvised armor or mismatched vehicles donated by various foreign governments that rarely come with replacement parts. Although about two dozen armored Humvees are due to soon arrive to the Iraqi soldiers here, advisers said the overall need for heavy equipment is much greater.

The Iraqi soldiers have little to rely on other than the U.S. military. There are no police officers working in most of the province, believed to be the insurgency's strongest base of support. And most of the soldiers in this Sunni-dominated region come from Shiite areas in the south, advisers said, despite efforts to make the force religiously representative of the country.

The small number of U.S. advisers — sometimes only a single American accompanies Iraqi soldiers during patrols — also has increased their exposure to danger. The team assigned to the 3rd Brigade has suffered a 20 percent casualty rate, Newell said.

The American teams have struggled to fill shortages of competent Iraqi officers, Newell said. Shortly before the Iraqi battalion commander was dismissed, Newell was forced to pull his trump card — withdrawing his advisers from the battalion — to force the Iraqi commander to stop reckless tactics such as traveling on roads known to have roadside bombs.

"Unfortunately, the (Iraqi) officers here are much like their soldiers — they're not in it for any sense of patriotism. They're doing this to get paid," Newell said.

An additional Iraqi army brigade is expected to arrive in Ramadi this spring, U.S. commanders said. But even as the army grows, larger and more violent areas await. In Ramadi, a city of about 300,000 people, the highway patrol is the only functioning part of the police department and security largely remains in the hands of U.S. troops.