Brussels, Belgium ? Bad as things are in Iraq, a quick U.S. departure would make them worse — encourage terrorists, set the stage for civil war, send oil prices spiraling and ruin U.S. credibility throughout the Middle East.

Nevertheless, U.S. allies and regional experts believe the rise in violence is a wakeup call for Washington to reconsider its Iraq strategy, including plans to hold key levers of power after sovereignty is restored June 30.

And some experts say President Bush must prepare the American people for a long, expensive and sometimes painful stay in Iraq.

“I think the U.S. is stuck in Iraq for a good decade,” said Juan Cole, a Middle East expert at the University of Michigan. “There is no way to get out.”

A quick U.S. departure would have a devastating effect on the war against terrorism. Washington has called Iraq the “main front” in that war and a fast exit would hearten Islamic extremists — regardless of the role they may actually be playing in the resistance.

From the southern Philippines to the Arab ghettoes of Western Europe, extremists would see a U.S. defeat as vindication of Osama bin Laden’s belief that Western democracies cannot stand up to the power of jihad.

U.S. allies such as Pakistan’s President Pervez Musharraf and Crown Prince Abdullah of Saudi Arabia might wonder whether it was safer to cut deals with their own extremists or risk having the Americans abandon them too someday.

“The U.S. will be perceived as having lost in Iraq, a perception that will have dire consequences for the region and U.S. strategic interests around the globe, especially the war on terrorism,” said Robert Rabil, a Middle East scholar.

Negotiations vs. force

Shiite Sheik al-Karbalie, right, leads thousands of Muslims in a chant against the United States during a joint Shiite and Sunni prayer service at the Um-al-Kura mosque in Baghdad. During Friday's service, Al-Karbalie denounced the U.S. military operation in Fallujah.

With less than 90 days until the scheduled handover of sovereignty, the United States and its Iraqi partners have not agreed on the makeup of a new government.

With the U.S.-led coalition in Iraq, power-sharing talks among Iraq’s religious, cultural and ethnic groups proceed at the bargaining table. Without the coalition, those groups may resort to guns.

Facing those threats would be an Iraqi security force incapable of maintaining security on its own.

After U.S. administrator L. Paul Bremer disbanded the Iraqi army, the coalition began organizing a new security force, which now numbers about 230,000 members — police, army, civil defense, border troops and security guards.

However, only about two-thirds have been fully trained and equipped. Privately, U.S. officials worry about their effectiveness. In Shiite towns, many police and security troops reportedly fled their posts, presumably to avoid fighting their own kinsmen.

Interested neighbors

With so much at stake, neighboring countries could not afford to stand aside.

The Iranians, believed to have ties to both al-Sadr and the Badr Brigades, would be tempted to protect their own fellow Shiites. That could force Turkey to intervene in the Kurdish north.

Syria and Saudi Arabia could not stand by and watch the interests of the Sunni minority suffer at the hands of a resurgent Shiite majority.

Shiite militancy in the south could spread throughout the Persian Gulf, especially to Shiite communities in Saudi Arabia’s oil-rich Eastern Province. Unrest in Iraq would delay the day when it could become a leading oil producer — adding to the upward pressure on world oil prices.

“Two-thirds of the proven oil reserves of the world are in the Persian Gulf,” Cole said. “It is not a place the U.S. can afford to have fall into chaos.”

The United States intends to keep a sizable military force in Iraq after June 30.