Except for a hardy band of neo-con optimists and the official apologists of the Bush regime, almost everyone is agreed that the United States has gotten itself into a nasty, self-wounding mess in Iraq where it is fighting a drawn-out guerrilla war it cannot win. At the same time, a large number of the critics of the U.S. invasion of Iraq, in the United States and in Europe, repeatedly say the United States cannot just “walk away.” That seems to mean maintaining U.S. troops and bases in Iraq for a considerable length of time while the United States tries, vainly, to enable the Iraqi government under its tutelage to assert some kind of reasonable control over its territory and restore a modicum of peaceful life to its citizens.

There is a long list of supposed consequences from walking away that all seem plausible on the surface. One is that it would result in unconstrained civil war in Iraq. This may be true, although many Iraqis feel they already are living in such a civil war, even with U.S. troops on the scene.

A second reason is that it would mean the takeover by al-Qaida-like jihadists in Iraq. This is a remote possibility. In any case, the presence of U.S. troops in Iraq has provided the main basis for recruitment of Iraqis into such organizations. The U.S. invasion led to their emergence within Iraq. As for Afghanistan, the Taliban were indeed there before U.S. troops arrived. They lost power in the central government as a result of the invasion. But they seem to be regaining it now, despite the presence of U.S. and NATO troops in some number. How long the NATO troops will be willing to stay is uncertain.

WITHDRAWAL FROM IRAQ WOULD MARK THE FIRST STEP TO HEALING THE SICKNESSES BROUGHT ON BY IMPERIAL ADDICTION.

A third reason is that a U.S. withdrawal would mean the strengthening of Iran’s position in Iraq and more generally in the Middle East. Most serious analysts feel that Iran already has been the biggest beneficiary of the U.S. invasion. It destroyed a serious opponent of Iran, Saddam Hussein. It has placed Shia and Kurdish groups in considerable power in Iraq, groups that have had close links with Iran and probably will continue to maintain and strengthen these links. There is no indication the U.S. presence is weakening Iran’s position.

A fourth reason is that withdrawal would hurt U.S. access to the oil supplies of the Middle East. However, the U.S. presence has led to a decrease in Iraqi production, which will not resume seriously as long as the war is going on. The decline in U.S. power resulting from the failed invasion has led Saudi Arabia, Iran, and other producers to begin to expand their role as a supplier of oil to China, India, and other countries, at the long-run expense of U.S. access.

A fifth reason is that withdrawal of U.S. troops and bases would be a humiliation of the United States, an acknowledgement of its defeat. It would be seen as a “betrayal” by those who fought and died in Iraq. The question is whether this is not happening already.

Let’s explore the alternatives the United States has. The only two realistic ones are eviction by the Iraqi government or “walking away.” With all the talk about irreconcilable ethnic rivalries in Iraq, we should not neglect the strength of Iraqi nationalism among both Sunni and Shia. After 2009, when they will see that the probable Democratic administration of the United States will continue to waffle about withdrawal, the pressure to find a united front of Sunni and Shia, which can only be constructed on the basis of the need to get out from under the U.S. omnipresence, is likely to become enormous. We already are witnessing the quiet negotiations going on in this regard. As for the Kurds, provided they retain a reasonable amount of autonomy, they reluctantly will settle for such autonomy as the best option in the existing situation.

What then would be the plus in “walking away”? First let us clarify what this means. It means a statement by the U.S. government that it will withdraw all troops without exception and shut down all bases in Iraq within, say, six months of the announcement date. Is this better than being evicted by a new government, resulting from a new nationalist alliance within Iraq? Yes. U.S. withdrawal would mark the first step on the long and difficult path to healing the United States of the sicknesses brought on by its imperial addiction, the first step in a painful effort to restore the good name of the United States in the world community.

Walking away will indeed be difficult and painful. But it is just as necessary for the United States to withdraw as it is for an alcoholic to withdraw, taking the first step on the path to renunciation of the addiction.

IMMANUEL WALLERSTEIN, SENIOR RESEARCH SCHOLAR AT YALE UNIVERSITY, IS THE AUTHOR OF THE DECLINE OF AMERICAN POWER: THE U.S. IN A CHAOTIC WORLD.