In the continuing violence, a car bomb ripped through a crowd of worshippers leaving a mosque in southern city of Najaf, killing at least 85 people – including a top cleric – and wounding 140. It was the deadliest attack since the fall of Saddam Hussein.
The CBS poll found that nearly half of Americans now think things are going badly for the U.S. in Iraq. That number has continued its rise since early last month.
Just 42 percent of Americans say the U.S. is in control of events in Iraq, while 47 percent think the U.S. is not in control. That's a drastic change in public perceptions since the end of April, when the war was still underway and 71 percent said the U.S. was in control.
Despite these concerns, the public still supports a U.S. troop presence in Iraq with only a third wanting the soldiers brought home. Most Americans favor more international involvement in Iraq, with 69 percent saying the United Nations, not the United States, should take the lead in setting up a new Iraqi government.
The poll had mixed results for the Bush administration. Most Americans think the White House has not been forthright about its dealings with Iraq, but the president's overall job approval rating is holding steady 55 percent, while 37 percent disapprove of the job he is doing.
In other developments:
The car bomb attack at the Imam Ali mosque, the holiest shrine for Shiites in Iraq, occurred just after Friday prayers.
The explosion destroyed nearby shops and dug a crater 3½ feet wide in the street in front of the shrine. People screamed in grief and anger as they searched the rubble for victims. Nearby cars were torn into twisted hunks of metal by the explosion.
"Even the Americans didn't bomb us like this!" wailed one tearful woman.
Among those killed was Ayatollah Mohammed Baqir al-Hakim, the leader of a moderate faction of Shiite Muslims locked in a dispute with more radical factions over whether to cooperate with American occupation forces. He died moments after he delivered a sermon calling for Iraqi unity and seeking Arab help to rebuild Iraq.
"I saw al-Hakim walk out of the shrine after his sermon and moments later, there was a massive explosion. There were many dead bodies," said Abdul Amir Jassem, a merchant who was in the mosque.
Both the al-Hakim supporters and a prominent figure in the U.S.-backed government blamed Saddam Hussein loyalists — not rival Shiites — for the attack.
The bombing followed the Aug. 8 attack on the Jordanian embassy in Baghdad, in which 19 died, and the Aug. 19 blast at the U.N. headquarters in the capital, where at least 20 perished.
The Al-Hakims are one of the most influential families in the Shiite community in Iraq.
Ayatollah al-Hakim was one of the most important Shiite clerics in Iraq. Abdel-Aziz al-Hakim, his brother, is a Governing Council member. He was leader of the armed wing of the Supreme Council for Islamic Revolution in Iraq, headquartered in Iran before the war. Ayatollah Mohammed Baqir al-Hakim, the slain cleric, was the leader of the organization and had been dividing his time between Tehran and Najaf.
There has been considerable unrest among the Shiite factions in Najaf, a holy city 110 miles southwest of Baghdad.
Younger Shiites, many from Baghdad's Sadr City slum, have conducted an ongoing power struggle with the more traditional Shiite Muslims in the city and region, conducting a political battle to grab control from the al-Hakim family.
Sheik Muqtada al-Sadr, who is not yet 30, and his young followers have sought tirelessly to replace more traditional factions as the voice of Iraq's Shiite majority, portraying themselves as the ones doing the most to redress decades of suppression by Sunni Muslims under the Saddam's rule.
There was no evidence Al-Sadr's group was connected to the blast.
Ahmad Chalabi, the head of the Iraqi National Congress and a Governing Council member, blamed U.S. forces for not keeping the region secure. Speaking on Al-Jazeera, also said Saddam supporters were behind it, saying they were trying to create sectarian discord in the country.
The top U.S. civilian official in Iraq, L. Paul Bremer, denounced the bombing, saying it demonstrated that "the enemies of the new Iraq will stop at nothing."
Friday's blast occurred one week after a bomb exploded outside the house another of Iraqi's most important Shiite clerics, a relative of the al-Hakim brothers, killing three guards and injuring 10 others, including family members. Rival Shiite factions denied having a hand in that attack, laying the blame on adherents of Saddam's Sunni branch of Islam.