To wage a just war, states must aim to punish aggressors or remedy a massive injustice. The goal is a more just situation than the one that existed before the resort to armed force, and the occupying power is obliged to do everything it can to prevent a worse outcome. Given this rough and ready framework of evaluation, what does an ethical exit require?
First, the country that has committed to, and completed, military operations must assess its degree of responsibility for the postwar situation. If its role was minor, its responsibility is proportionately diminished. In the case of Iraq, of course, the United States and its allies bear the heaviest burden. The United States in particular has a direct responsibility for postwar Iraq that no other country or organization shares. This state of affairs is obviously not ideal. A major power should bring as many allies on board as possible when it commits to war. Given what we know of U.N. stalling and ineptitude where dictatorial regimes are concerned, however, the formal involvement of the international community will often be impossible. The international community has a huge stake in the outcome and should help rather than hinder, but ultimate ethical responsibility lies with the powers that unseated Saddam Hussein.
The countries responsible for the postwar situation bear a major burden in repairing infrastructural and environmental harm that is the direct result of military operations. Civilian affairs teams should first concentrate on the basic necessities of life -- water and electricity, and then schools, hospitals, and other basic institutions of civic order. Repairing the political infrastructure is just as essential to creating a just peace. That means leaving the people in the invaded country, as well as the wider international environment, in better shape than before the intervention. Installing legitimate authority in Iraq is a delicate balancing act.
The occupying powers must also provide defense and security. If a country has been disarmed, the occupying power has taken on responsibility for its security and protection from external and internal enemies. How long this provision will be, and how extensive, will depend on the threats it faces and the speed with which Iraq can rebuild its own defense and internal security capability.
Finally, the occupying powers must react if yet another Saddam-type regime of fear begins to emerge. Even as the United States protected postwar Western Europe -- including a new democratic state in West Germany -- throughout the Cold War and decades of bipolarity, so the United States must remain tightly tied to a new Iraq. Just as the Allies would never have permitted a Nazi state to reemerge in Germany, so must the United States show vigilance with Iraq, should internal forces of stability and decency falter and collapse. The Iraqi people must not be victimized again.