House and Senate Democrats over the next several weeks will reconcile their versions of a massive supplemental funding bill for U.S. military operations in Iraq and Afghanistan. President Bush, meanwhile, has threatened to veto any compromise that includes deadlines for withdrawing U.S. troops.

Normally, we would be skeptical of attempts by Congress to write war strategy into law -- as opposed to exercising its Constitutional duties to declare and finance wars. But these are not normal times. President Bush continues to run the war as if the 2006 midterm election didn't happen, and as if the U.S. Congress doesn't matter. This all-too-characteristic display of stubbornness and unilateralism has invited a forceful response from the new majority.

Democrats are rightly determined to reassert Congress's oversight role and hold the administration to a much higher standard of accountability on Iraq, and indeed everything else. At this point, that's more important than the particulars of either the House or Senate bills.

As we've repeatedly made clear, we're no fans of fixing artificial deadlines for troop withdrawal. But the timelines in the House and Senate bill include significant exceptions -- to win the support of moderate Democrats -- and envision the need for the United States to keep some forces in Iraq after major combat units leave.

Instead of haggling over deadlines, Congress and the White House should be trying to hammer out a bipartisan strategy for winding down the U.S. military engagement in Iraq. Taken together, the House and Senate bills offer a road map -- roughly consistent with the Iraq Study Group's recommendations -- for gradually reducing America's military presence in Iraq. This approach has more support in this country than the president's plan for "victory."

Having strongly reasserted Congressional prerogatives and oversight, however, Democrats need to avoid being drawn into a contest of political brinkmanship with the White House. If Bush makes good on his veto threat, some Democrats will likely favor a tactic of sending the same bill back with the same conditions, defying him to deny the troops funding in an obstinate effort to insist on his own, failed approach to Iraq. But this approach would touch off a political and perhaps a constitutional crisis that Congress may not win, while risking support for the practical needs of our troops in the field. Sen. Barack Obama is right: Regardless of the truly high stakes of this dispute, Washington should not play "chicken" with funding for our troops.

Besides, there are more constructive ways for congressional Democrats to use their power of the purse. We urge lawmakers to take these steps following an expected presidential veto:

First, they should quickly pass a short-term and clean supplemental appropriations bill that will simultaneously give the troops what they need while forcing the president to come back and ask for more funding in three months. That will give Congress a chance to evaluate the administration's "surge" of troops into Iraq, which administration officials have assured us will show results by late summer. This is the logic of the proposal by Reps. Dennis Cardozo (CA) and Mike Ross (AR), which is under consideration by the House Democratic leadership.

Second, Congress should examine not only whether security has improved in Baghdad, but also whether the Maliki government has made a good faith effort to reconcile Iraq's Sunni community to the post- Saddam political order. While there is too much glib talk about forcing the government to somehow deliver a "political solution" to the war, there's no doubt that real progress on the political front, more than U.S. troop levels, is the key to stabilizing the country.

Third, congressional Democrats should call for a diplomatic strategy to accompany the administration's military strategy in Iraq. For four long years, we've been fighting in a regional and international diplomatic vacuum. This makes absolutely no sense.

The valiant efforts by U.S. forces to provide security within Iraq must be reinforced from without. The international community, led by the United Nations, needs to weigh in, politically as well as economically. More than either the Maliki government or the United States, the United Nations has the political legitimacy to mediate among Iraq's conflicting groups and try to negotiate a peace settlement. Even if it doesn't yield dramatic breakthroughs immediately, a credible, internationally backed "peace process" would be harder for insurgents to reject than "occupation" by the United States.

Negotiations would focus on oil revenues, de-Baathification, amnesty for "nationalist" insurgents, constitutional changes, and the disarmament of militias. The United Nations also needs to work with Iraq's neighbors and donor countries to devise strategies for taking care of the 2 million Iraqi refugees who have fled to nearby countries, and the nearly 2 million that have been displaced internally.

The bottom line is that congressional Democrats are rightly engaging the Bush administration and its Republican allies in an effort to force a fundamental change of strategy in Iraq that will wind down our conventional combat presence while giving Iraqis a decent chance to take charge and survive. They should approach this inherently difficult but essential task in a way that makes a mockery of administration and Republican claims that the only options are to support the president or cut off funds entirely. Democrats cannot totally impose their will so long as George W. Bush clings to power. But they can expose his stubborn folly in the court of public opinion, which he cannot forever defy.