Lawrence J. Korb

was assistant secretary of defense in the Reagan administration and is now a senior fellow at the Center for American Progress

Sean E. Duggan

is a research associate at the center

It is becoming increasingly clear that any bilateral U.S.- Iraqi Status of Forces Agreement will have to include a date certain for withdrawal.

Following Iraqi Prime Minister Nouri al-Maliki's demands last month, Iraqi Foreign Minister Hoshyar Zebari emphasized this week that the United States must provide "a very clear timeline" as part of any agreement allowing the United States to retain a military presence in Iraq past this year.

The United States must seize this opportunity and allow the Iraqis to take control of their own security by beginning a responsible phased withdrawal of U.S. combat troops from Iraq.

To capitalize on gains made in Iraq, the United States must use a withdrawal timetable as leverage to force political change in Iraq while pushing Iraq's competing powers to recalculate their self-interest in light of the withdrawal.

Yet there is still significant disagreement and confusion about how long a withdrawal would take. Despite the assertions of those who wish to remain in Iraq indefinitely, a massive yet safe and orderly redeployment of U.S. forces, essential equipment and support personnel is within the capabilities of the U.S. military and could be achieved efficiently and safely over eight to 10 months.

In fact, if the U.S. military had to withdraw to Kuwait as quickly as possible, it could get out of Iraq within three months by conducting an "invasion in reverse." Such an exit, however, would sacrifice a significant amount of sensitive equipment and create an instant political and security vacuum similar to that created by Saddam Hussein's overthrow. While feasible, that's not a preferred course.

Rather, if the U.S. military were ordered now to begin planning a phased redeployment from Iraq, it could safely be completed by July 2009. During this period, the military would not replace outgoing troops as they rotated home at the end of their tours; that would draw down by two brigades per month - a pace similar to previous rotations conducted by our military in the last five years.

The eight- to 10-month time frame is based on two critical assumptions. First, the primary objective of a U.S. withdrawal is to get soldiers and Marines to Kuwait safely. Those advocating that we remain in Iraq indefinitely have noted that U.S. facilities in Kuwait are capable of loading and exporting the equivalent of only one brigade per month. But getting soldiers and Marines to safety in Kuwait in the first place matters more than ensuring that one unit's equipment is shipped out before another unit can exit. Once soldiers, Marines and their equipment are safely in Kuwait, the main objective of leaving Iraq will have been accomplished.

Second, ours is not a "no Forward Operating Base left behind" strategy. Withdrawal time will depend largely on the amount of equipment the military decides to take with it. Sensitive equipment yes - but the military need not remove every blast wall, refrigerator and Portajohn from every base in Iraq. Better to take a cost-effective approach to redeployment.

Such large troop and materiél movements are not without precedent in Iraq. In the first half of 2004, the Pentagon moved more than 235,000 soldiers and their equipment in and out of Iraq as the forces who led the invasion reached the end of their one-year deployment. During the six months of the rotation, U.S. forces suffered 15 percent lower casualties than in the six months that followed. Similarly, current U.S. casualties in Iraq have reached their lowest levels since 2004 while the last five combat brigades involved in the surge have rotated home in the last five months.

A phased redeployment of U.S. forces has at least three advantages. First, a withdrawal is a conventional operation that plays to the strengths of the U.S. military. The Army's institutional and operational strengths rest on both advanced logistics and maneuver tactics, strengths crucial to a redeployment.

Second, a phased redeployment does not leave a sudden and immediate power vacuum in the country. By putting the Iraqi government and its neighbors on notice that they - not the United States - will be responsible for the consequences of Iraq's internal stability, our country would give all players an incentive to start doing just that.

Third, a phased redeployment would enhance security for U.S. forces. While military planners plan for the worst, it's at least possible that the climate for a withdrawal will be relatively secure, especially since all Iraqi parties want the United States to redeploy either immediately or over a year and would have no incentive to create conditions that would hinder withdrawal.

When President Bush repeatedly stated that the United States "would not stay one day longer than the Iraqi government desires," he never believed the Iraqis would ever publicly call on the United States to go. Now that they have done so, this country can and should begin an orderly and safe redeployment to regain control of its security interests in the Middle East.