The ambassador warned of a calamitous disruption in the production and transport of energy supplies in the Persian Gulf. He described a worst-case scenario in which religious extremists could take over sections of Iraq and begin to expand outward.
"That would make Taliban Afghanistan look like child's play," said Khalilzad, an American of Afghan descent who served as U.S. envoy to Afghanistan before taking on the post in Iraq.
The U.S. vision for a broad-based government "reflects the aspirations of the [Iraqi] people," he said. "If we were at variance with the aspirations of the people, we'd be in trouble."
Khalilzad said U.S. officials had tried to enlist the support of governments of neighboring countries, even exploring "modalities of setting up a meeting" with Iran. He named Iran and Syria as two nations that had been "particularly unhelpful" in Iraq.
On Monday, Iraqi politicians continued to wrangle over the composition of a new government. Interim President Jalal Talabani announced a decision to convene parliament on Sunday, only to be quickly countered by Shiite political leaders who asked him to postpone the session.
Shiites have nominated interim Prime Minister Ibrahim Jafari to serve a full term. Kurds and Sunnis have pushed to derail his candidacy.
Khalilzad described such day-to-day political jousting as healthy. "They are bargaining. They are shadowboxing," he said. "This is a much better way than with guns."
Still, the politics of the gun spoke loudly Monday.
Violence, much of it with sectarian overtones, left at least 18 Iraqis dead across the country as multiple car bombs exploded. One U.S. soldier was reported killed in a combat incident in western Iraq.
Maj. Gen. Mubdar Hatim Hazya Dulaimi, commander of the Iraqi army in Baghdad, was killed in western Baghdad, the U.S. military announced.
He was killed by a single bullet while driving in a long convoy shortly after 5 p.m., said Mohammed Askari, a Defense Ministry advisor.
Dulaimi, a Sunni, commanded a force that is seen by many as a counterweight to that of the Interior Ministry, whose Shiite-dominated police and commando units have been accused of extrajudicial killings.
The U.S. military reported Monday that a U.S. soldier had died Sunday as a result of "enemy action." The soldier was killed in rural western Iraq, although much of the insurgent violence in the country has shifted to religiously diverse urban areas, said a U.S. official who requested anonymity.
