Military officials are anxiously watching the brittle partnership between Sunni and Shiite Muslims in Iraq as U.S. analysts warn that renewed waves of violence have put the country at a crucial crossroads.
Sunni militants are widely thought responsible for bombings in Baghdad last week that left 95 dead. But a key question being debated in Washington is whether the larger Sunni community has begun implicitly supporting the attacks.
For the moment, military officers and American analysts do not believe that a new sectarian war has broken out. But the U.S. withdrawal from Iraqi cities June 30 has unnerved Sunnis who saw the American presence as protection against Shiite oppression, and experts hope Prime Minister Nouri Maliki finds a way to quickly calm Sunni fears.
"This is a very dangerous moment, and this thing could easily get out of hand," said Stephen Biddle, a scholar at the Council on Foreign Relations who has advised military commanders.
American officials and analysts are worried that continued strife could further strain ethnic and religious relations and threaten programs that have proven vital to tamping down violence.
U.S. options are limited because Maliki's Shiite-dominated government reportedly opposes any resumption of U.S. high-profile troop patrols in urban areas.
Iraq's sectarian war cooled in 2007 after Sunnis began to refuse to help militants, denying them access to hide-outs and cutting off their ability to travel freely.
"Now that we see this stuff happening again, I think there is a distinct possibility that Sunnis who refused to tolerate violence have decided to allow some of it again," Biddle said.
Garnering Maliki's full support for the U.S.-backed initiative to organize former Sunni insurgents into local security forces, known as Sons of Iraq, is an especially crucial issue, said military officials and analysts.
Members of the Sons of Iraq originally were on the U.S. payroll. The Iraqi government assumed responsibility for the 95,000 people in the program in April, and is slowly integrating them into its security forces and government ministries.
But Maliki's government has long had misgivings about the program, worried it was arming and paying former insurgents and members of Saddam Hussein's Baath Party.
Nonetheless, 13,000 Sons of Iraq troops so far have been made part of the Iraqi security forces. An additional 3,300 have been given positions in government ministries.
American military officials in Baghdad consider the program to be on sound footing, but sectarian divisions remain.
"It would be nice to think that they would integrate completely and they would move forward without tension and pressure, but I do not know if that is possible," said a military official, speaking on condition of anonymity because of the sensitivity of the situation.
Some analysts said Maliki's hesitation to move more quickly to place Sunni forces in government posts and security forces could lead to some frustrated Sunnis dropping out and returning to the insurgency.
Maliki has been supportive of the program, especially in rural areas where Sunnis are organized more along tribal lines, some analysts said. But he is considered more skeptical about Sunnis in urban areas such as in Diyala province, northeast of Baghdad, where the insurgency was more violent and politically organized.
"Maliki's reluctance to integrate the Sons of Iraq in Diyala has been noticeable," said Kimberly Kagan, a frequent advisor to military commanders in Iraq and the founder of the Institute for the Study of War. "Maliki has very carefully targeted key leaders of the Sons of Iraq and he has arrested some of the more prominent leaders."
But Kagan and her husband, Frederick Kagan, a scholar at the American Enterprise Institute, said that even as Maliki has squared off against Sunnis in Diyala, he has offered a political alliance to others.
"Maliki is actively courting Sunni political leaders," said Fred Kagan. "The bottom line is right now all of these issues are playing out in the political arena."
On Sunday, the Iraqi government broadcast a video confession by a man who claimed to be the mastermind of one of the bombings Wednesday, at the Finance Ministry. He said he was a member of the banned Baath Party, which he claimed to be working to reactivate in Diyala province. He said he had been acting on orders from an Iraqi Baathist in Syria.
There was no way of independently confirming the account, and the authenticity of such confessions has been called into question in the past.
Biddle sees signs of deeper tensions in the recent blasts.
"I look at these bombings and one distinct possibility is that the Sunni community is signaling Maliki that their interests have to be respected and there are costs to running roughshod over Sunnis," he said.
A renewed U.S. military presence on the streets of Baghdad could reassure Sunnis. "But we have to be asked [by the Maliki government] and we have no ability to insist," Biddle said.
U.S. military officials downplay any likelihood that U.S. forces will return to their previous profile, citing the strong political opposition within the Iraqi government.
Fred Kagan said it would be "disastrous" for the overall U.S. strategy to return to the cities.
"We have dealt ourselves this hand; this is what playing it looks like," he said. "We will have to play better."
Times staff writer Liz Sly in Baghdad contributed to this report.