As Iraq prepares to install an elected government, and Congress evaluates the latest bill for $80 billion, many Americans are asking when the troops will come home. Our exit strategy depends on our entry strategy: When we leave depends on why we went.

The Bush administration has struggled to answer this question, giving multiple explanations, some valid, others not: the imminent threat of weapons of mass destruction; combating terrorism after 9/11; regime change; and now promoting democracy. The problem is that every change in the political objective moved the goal posts for the military.

Secretary of Defense Rumsfeld is correct that our departure should be guided not by the calendar, but by results on the ground. However, the Bush administration now needs to outline more specifically what the U.S. military must accomplish over the next year – or longer – before we should declare mission accomplished (again).

Building Iraqi security capabilities and democratic institutions is important, but the emphasis must be on U.S. security, not Iraq's. For example, having greatly exaggerated Saddam's marginal links to terror networks before the invasion, we can't leave Iraq with jihadists holding center stage and in a stronger position to threaten us over the long term. Reviewing our primary reasons for going, what does the military to-do list look like?

Weapons of mass destruction. Whether or not Iraq was ever an imminent threat, it isn't now. Saddam's statue and government fell in April 2003. He was captured eight months later. The Iraq Survey Group's final report will conclude that there were no weapons of mass destruction and whatever capability Saddam did have has either been destroyed or has migrated somewhere else. That complicates our nonproliferation challenge, but is a problem for another day and country. We need to find constructive employment for Iraqi scientists so that they don't sell their knowledge to other nuclear wannabes, perhaps a task that can bring the International Atomic Energy Agency (IAEA) back to Iraq.

Terrorist safe haven. President Bush said again during the State of the Union address that we "are fighting terrorists in Iraq, so we don't have to face them here at home." If he's right, why do we call it the global war on terror? But there is no doubt that we now confront them in Iraq, a self-fulfilling prophesy. An estimated 1,000 foreign fighters, led nominally by Mus'ab al-Zarqawi, have infiltrated since the invasion. The National Intelligence Council says that Iraq is now a training and recruiting ground for the next generation of terrorists. If Iraq is the central front in the war on terror, meaning our security is directly affected by the outcome there, then our job in military parlance is to "win decisively" as a prerequisite to withdrawing U.S. military forces. This is not a mission we can delegate to untested Iraqi security forces. We can't leave a more extensive and dangerous terrorist infrastructure in place than existed before the invasion. But the Bush administration has yet to develop an effective counter-insurgent strategy. In fact, given the return of violence to pre-election levels, a case can still be made that we need to add more troops to defeat al-Zarqawi now.

Democracy in the Middle East. "We are in Iraq to achieve a result," the president outlined at the State of the Union. "A country that is democratic, representative of all its people, at peace with its neighbors, and able to defend itself." The final element is the only one that the military can directly influence. Training, equipping and mentoring Iraqi forces so that they can assume the lead security role in Iraq is our de facto exit strategy. After a yearlong false start under the Coalition Provisional Authority, the military training programs under Army Lt. Gen. David Petraeus are advancing, just not fast enough. Unfortunately, some traditional allies who were spurned at the start are not going to help the Bush administration get out of Iraq any faster, even with the current thaw.

Meanwhile, the election actually increased the immediate security challenge for U.S. forces. There is a new and larger Iraqi government to protect. The constitutional process will require public involvement, robust debate and political compromise, none of which is possible in the current atmosphere of violence. The primary long-term risks to democracy are internal to Iraq – Sunni rejection of an Islamic state; Shia rejection of Kurdish autonomy; or a Kurdish declaration of independence, any of which can ignite a broader civil war than currently exists. But resolving these issues will depend primarily on political will, not military muscle.

The Bush administration underestimated what we would confront in Iraq, winning the war and fumbling the peace. Having been burned before the invasion for predicting a cakewalk, now it pretends that questions of even estimating how long troops will be necessary in Iraq or what future operations will cost. A fixed timetable is not realistic, though even the Iraqis are suggesting that they will be ready to take over security within 12 to 18 months. The American people deserve better answers.

Just go back to the beginning. Why did we go in the first place?

P.J. Crowley is a senior fellow and director for national defense & homeland security at the Center for American Progress. He is a retired Air Force colonel and served in senior positions at the White House and Department of Defense during the Clinton administration.

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