BAGHDAD (Jan. 21, 2009) -- Iraq's bloody civil war worsened today, when 10,000 heavily armed troops from the Shiite state of Shiastan pushed north from Najaf and Rumaythah. The attack threatened to trap three battalions of U.S.-backed Sunnis in the region.

The latest round of fighting has triggered a new wave of refugees into Kuwait and Jordan, the United Nations reported today. Millions of Iraqis have fled the country since American troops pulled out in 2006, a controversial withdrawal that al-Qaida celebrates as a watershed victory.

Word of today's offensive pushed crude oil prices to $210 per barrel, a new record, certain to cause problems for the newly inaugurated American president . . .

All right, enough with the doom and gloom. The preceding paragraphs are fiction, but they reflect what's likely to happen if the United States pulls out of Iraq before the country is stabilized and able to function on its own. Unfortunately, some of our politicians want to do exactly that.

"We believe that a phased redeployment of U.S. forces from Iraq should begin before the end of 2006," House Minority Leader Nancy Pelosi and Senate Minority Leader Harry Reid wrote in a letter both signed in August. Even if our task there remains unfinished?

As President Bush put it on Oct. 11, "when you pull out before the job is done, that's cut and run as far as I'm concerned. And that's cut and run as far as most Americans are concerned."

Heritage Foundation experts James Carafano and James Phillips explained in a recent paper what's likely to happen if we withdraw quickly. "Such a shortsighted U.S. policy would be a severe blow to the Iraqi security situation, Iraqi oil exports, U.S. allies in the region, the global war against terrorism and the future of all Iraqis," they write.

If we leave now, we'd leave the Iraqi army (with all its heavy weapons) up for grabs. That's likely to spark a civil war, as soldiers align themselves into religious and regional militias.

Under that scenario, we can expect Iran -- already a regional power -- to support the Shiite Muslims in the south, a move that would give Tehran control of most of Iraq's oil. Not that this would necessarily keep the oil flowing; as the civil war escalated, guerrillas would cut pipelines and blow up oil wells.

Now, Iraq produces 2.5 million barrels of oil per day, and the country's government aims to increase that to 2.7 million by year's end. If production is disrupted, though, worldwide prices would skyrocket.

If we cut and run, Iraqi civilians would be the biggest losers. Millions would flee the starvation, disease and destruction that civil war brings. Meanwhile, al-Qaida would tout its role in forcing the United States out, providing a huge recruiting boom for the terrorist group.

This doesn't mean we should stay indefinitely. As they say, there are only two "exit strategies" from any war: A country can win and go home, or it can lose and go home. Either way, all our troops eventually will exit Iraq. What really matters is what they leave behind.

We've made progress in Iraq, and we'll continue to do so. Many of al-Qaida's senior leaders have been killed or captured and the group's popularity among the Iraqis is low. We need to keep training Iraqi forces and preparing them to stand on their own.

In the long run, only Iraqis can assure the success of Iraq. But if, in the short run, we cut and run, we guarantee failure -- for them and for us. We can avoid the bleak future outlined above. But we must steel our resolve to get the job done right.

Edwin Feulner is president of The Heritage Foundation (heritage.org), a Washington-based public policy research institute and co-author of the new book Getting America Right.