To this end, top U.S. authorities in Baghdad have urged the new Shiite-led government in private, high-level meetings this week to move quickly to further involve Sunnis in the governing process, according to U.S. officials familiar with the talks.
Supporters of Jafari's government insist there is progress being made in the fight against insurgents. Iraqi security forces release an almost daily accounting of weapons caches seized and alleged terrorists arrested, including several described as high-ranking aides to Abu Musab Zarqawi, a Jordanian who leads the militant group al Qaeda in Iraq.
"It is true the Iraqi security forces are not qualified enough to face these waves of terrorism, but with the cooperation of the multinational forces, the security situation will be improved," said Ali Dabbagh, a National Assembly member from a leading Shiite party. "And we can see it improving now."
The surge in suicide attacks continues to be characterized by U.S. military intelligence specialists as largely the work of foreign fighters, often in partnership with Iraqi militants. But several senior officers with access to intelligence reports acknowledged considerable uncertainty about which groups are behind the attacks.
In an effort to choke off the infiltration of foreign fighters along the border with Syria, U.S. Marines have been engaged in an extensive operation this week in northwestern Iraq. Casey visited the border region Thursday and highlighted plans to move much of the U.S. Army's 3rd Armored Cavalry Regiment there from the Baghdad area.
In recent weeks, the bloodiest attacks have affected ordinary Iraqis, perhaps because they are most vulnerable, U.S. military officials say.
"It's really now a war against the Iraqi people conducted by foreigners," said Lt. Col. Steven Boylan, a spokesman for coalition forces in Iraq. "The only thing that is left for them is to try to drive a wedge between the Iraqi government and Iraqi people by targeting Iraqi people."
Insurgents' tactics have recently reflected greater coordination and sophistication, Boylan said. They have begun detonating car bombs with drivers who did not plan to be suicide bombers but allegedly were expecting to hand off the vehicles to someone else.
"We have reorganized ourselves since the Fallujah battle," said a man who identified himself as Abu Nasir, 46. He said he had been a colonel in Hussein's army and is now a leader of the Salahuddin Platoon, a guerrilla group linked to Zarqawi. "We've decided not to give them a chance to live in peace as long as we are here."
Here in Baghdad, where the frequency of attacks has been the highest in recent weeks, people have been forced to adjust to violence that has become as disruptive as it is unavoidable.
"It is getting to be too much. I have to change the route I use to go to work every day," said Jowad Abdul Rahman, 48, after Friday prayers at one of the city's largest Sunni mosques. "The insurgents do not care if there will be innocent people in their way."
In the neighborhood of Jaderia, which seems a world away from the violence splashed across his television screen, Mahmoud Ahmed Uthman described the most recent meeting of what he calls his "Thursday group."
Over breakfast almost every week for 15 years, he and a handful of friends have met in each other's homes to debate the issues of the day. Under Hussein's rule, he said, the gatherings were a sanctuary from the persistent horrors of daily life.
They have become so again.
"We talk about literature, commerce, many topics. But on all of our minds now is the insurgency," said Uthman, 73, as what sounded like a mortar round momentarily drowned out the Vivaldi concertos on his stereo. "We ask, why is this happening? How can this be stopped to save Iraq?"
Staff writer Caryle Murphy and special correspondents Omar Fekeiki, Bassam Sebti and Nasseer Nouri contributed to this report.
