WASHINGTON -- Arguments for and against an American military withdrawal from Iraq will run deep and loud this week as Congress takes up the issue of when and how U.S. troops should be brought home. But there has been virtually no consideration of the costs and risks of a withdrawal, whether it comes soon under congressional deadline or later as a tactical military judgment.
Military officers and logistics experts, many speaking privately because of the political sensitivity of the subject, said that chaos, confusion and casualties could mark the withdrawal of American troops, depending on how long the military has to plan for withdrawal and on the pace and scale of fighting in Iraq.
Under the best circumstances, lines of roughly 1,000 Abrams tanks and Bradley Fighting Vehicles, along with 20,000 Humvees and tens of thousands of trucks would snake south toward Kuwait, with helicopter gunships overhead and tanks guarding key intersections, a logistical nightmare that would last six months or longer.
An abrupt retreat could trigger widespread looting, especially of abandoned American military facilities and equipment, as U.S. troops depart. Similar fates have befallen abandoned British bases in southern Iraq.
A U.S. withdrawal could also alarm those Iraqis closely identified with the American war effort, sparking desperate efforts to get out. Specialists who have studied the problem say streams of refugees could clog the roads, as troops fight their way out through swarms of insurgents, some specialists said.
Either way, once a withdrawal is announced and under way, it could be difficult for commanders to maintain morale and fighting spirit in their troops - both American and Iraqi.
"Once you start down this road, whether you are going to be able to set the pace of events with a rheostat strikes me as a pretty dicey proposition," said Thomas Donnelly, a military specialist at the American Enterprise Institute, a policy think-tank in Washington. "Naturally, it would induce great caution among commanders."
Once a pull-out is apparent, he added, "Who is going to take the risk of living in a police station in a Baghdad neighborhood?"
"At the end of the day, what we do will be shaped by the enemy, as in all wars," said retired army Maj. Gen. Robert H. Scales, a senior military strategist and author.
The measure at issue on Capitol Hill this week is a $124 billion package of legislation that would continue funding for the war for six months, but mandate a troop withdrawal beginning as early as December if certain benchmarks aren't met. The legislation demands that a troop withdrawal be completed by August 2008.
Both foes and advocates of a quick withdrawal have described this complex operation in simple terms, as Bush did yesterday when he said it would be "tempting" to "pack up and go home." Opponents of the war have campaigned on the slogan, "Bring the Troops Home Now."
"This legislation for the first time sets a date for the responsible redeployment of American troops from Iraq," House Majority Leader Steny H. Hoyer of southern Maryland said yesterday. "It is past time - way past time - for a new direction in Iraq," he said.
Bush, who said he had talked early yesterday with Lt. Gen. David Petraeus, the U.S. ground commander in Iraq, as well as Iraqi Prime Minister Nouri al-Maliki, acknowledged that "prevailing in Iraq is not going to be easy." But Bush insisted that the war, which over four years has killed 3,218 American troops and wounded 23,417, "can be won. It will be won if we have the courage and resolve to see it through."
The debate over an American withdrawal, which has seesawed through Congress without resolution for months, rides public opinion polls showing that a majority of Americans oppose keeping U.S. troops in Iraq.
Some politicians have argued for a complete pull-out. Others, including Democratic presidential contenders Sen. Hillary Clinton and Sen. Barrack Obama and GOP Sen. John E. Sununu of New Hampshire, argue for a "phased withdrawal" that would pull out combat brigades first, leaving in place the tens of thousands of U.S. military personnel serving with Iraqi units as trainers and advisers, and supporting the Iraqi army with logistics, air cover, intelligence and medical treatment.
"I think the goal of withdrawing [all American] combat troops by the end of 2008 is very realistic and attainable," Sununu told the New Hampshire Union-Leader in a story published Sunday. "I think it would be foolish for anyone to predict a day when there would be zero" American troops in Iraq, the Union-Leader quoted him as saying in a phone interview from Baghdad.
Other proposals call for one or more U.S. combat brigades to be staged "over the horizon" in remote parts of Iraq or even across the border in Kuwait as "quick reaction forces."
But military experts doubt the effectiveness of trying to withdraw only combat troops, citing the effect on the safety and morale of these Americans left behind, particularly the small teams of advisers embedded with Iraqi units.
"I don't think that advisory team in downtown Baghdad is going to want to go in without the knowledge that there is some firepower back there to help them out," said Marine Lt. Col. Stephen Sklenka, who recently returned from service in Iraq.
Instead, some experts argue that with civil-war passions running deep and bitter in Iraq, only a delicate and gradual reduction of U.S. forces can minimize chances for a collapse. That means ensuring that Iraqi army and police units can take up responsibility as Americans depart.
"You don't want to see U.S. or Iraqi capabilities plummet precipitously," said Nora Bensahel, senior political scientist and military expert at the Rand Corp., a nonprofit research center. "A gradual withdrawal would minimize the incentive for the adversary to increase the violence."
Last summer, in a development that caught the eye of U.S. military planners, armed looters ransacked two military bases in southern Iraq hours after British forces had pulled out.
The United States has built several military compounds in Iraq complete with fast-food outlets, supermarkets, gyms, vast mess halls and chapels with stained glass windows. Several bases have vast storage and maintenance depots and airfields that are beyond the capability of Iraq's present military to operate, logistics officers said.
The fate of these facilities is unclear. The last time the United States undertook a massive military withdrawal was at the end of the Vietnam War, where the redeployment of troops and equipment was accomplished in a series of phased movements between 1970 and 1972. That experience provides a grim lesson.
By 1972, according to an internal Army report, depots in South Vietnam "were swamped" with gear abandoned by evacuating units, and more than 2,500 vehicles, 60,000 small arms as well as helicopters, artillery, boats and ammunition were turned over to the South Vietnam military.
"The South Vietnamese had a tendency to plunder their own nest, and many U.S. bases being evacuated were stripped by South Vietnamese soldiers," according to the report, from the files of the U.S. Army Center of Military History.