The bombing of a Shiite shrine, which threatens to plunge Iraq into all-out civil war, highlights the U.S. military's failure to create a safe environment for rebuilding the nation.
"This failure created a security vacuum that has never been properly filled and that is the single greatest underlying problem in Iraq today," says a new report by the Brookings Institution.
That was chillingly evident Thursday as violence continued to wrack the country. Shiite militias have burned more than 168 Sunni mosques in reprisal for Wednesday's bombing that ruined the Golden Mosque in Samarra, sacred to Shiite Muslims. Revenge killings have claimed at least 111 lives, among them 10 clerics.
Many experts say the military's focus on chasing insurgents has also helped push Iraq into a state of anarchy from which it will be hard to recover.
"By the nature of our military operations, we have in a sense already lost the war," said retired Lt. Gen. Robert Gard, a senior fellow at the Center for Arms Control and Non-Proliferation.
"You misuse firepower and kill a bunch of civilians and they recruit more than you kill. That's why - despite the thousands of insurgents we claim to kill - the estimated strength has not gone down."
After failing to find weapons of mass destruction - the reason for invading in 2003 - the Bush administration shifted its focus to building a stable, democratic Iraq. The country now has an elected Parliament and a constitution that guarantees basic rights and freedoms.
But the lack of security has severely hampered reconstruction and makes daily life an ordeal. Electricity is still three hours on, three hours off in many places. Oil production is almost 25 percent below pre-war levels. Many reconstruction projects have been scaled back or eliminated because money has been shifted to security improvements.
The Brookings report faults the military for concentrating too many troops in Iraq's western provinces, where "the insurgents are thickest and support for reconstruction is thinnest." The lack of security in other areas has forced even moderate Iraqis to seek protection from Shiite, Sunni or Kurdish militias, which engage in the kind of sectarian violence now sweeping the country.
To defuse the power of the militias, U.S. troops should concentrate on making Baghdad and other target cities safe enough to "emerge as successful models of reconstruction," the Brookings report says. From there, reconstruction would spread across the country "like an ink blot" as more security forces become available.
That approach is based on a classic rule of counterinsurgency: Guerrillas cannot be defeated by military means alone. Though the Brookings' idea is sound, it may be "a day late and a dollar short," as one military expert puts it.
"We don't have enough troops to do it," says Lawrence Korb, senior fellow at the Center for American Progress.
"It would have been great if they had done it right from the beginning, but I just don't know that we have the credibility now."
Korb, assistant secretary of defense in the Reagan administration, advocates setting a timetable for U.S. withdrawal. Although some special operations forces would remain "in case Iran invades," half of the 136,000 U.S. troops now in Iraq would leave this year and most of the others would be out by the end of 2007.
Forces then would be redeployed around the region to respond to emergencies and fight terrorism in other countries.
"A timetable would provide an incentive," Korb said. "As long as we're there, there's no incentive for (Iraqis) to get their act together."
To those who say pulling out would lead to civil war, another expert had this rebuttal:
"Iraqis are already fighting Iraqis. Insurgents have killed far more Iraqis than Americans. That's civil war," wrote William Odom, head of the National Security Agency under President Ronald Reagan.
"We created the civil war when we invaded: We can't prevent a civil war by staying."
Despite the worsening situation, President Bush so far faces little pressure from either politicians or the public to end the war.
Democrats have been slow at making Iraq an issue that could help them pick up seats in November's midterm elections.
"The Democrats have this huge problem: They are scared of being called soft on terrorism and weak on national defense," said Kevin Martin, executive director of the antiwar group Peace Action.
On the Republican side, support for a quick pullout or any major shift in policy is even more muted. Still, Republicans worry about Iraq and fear it could yet become a major election issue, said Charlie Cook, editor of the Cook Political Report. The war already has helped drag down Bush's approval ratings, which are among the lowest for any second-term president.
"You cannot find a Republican strategist who won't admit, at least privately, that the political climate is pretty bad for Republicans," Cook said.
For now, members of Congress are hearing little clamor from constituents to pull out of Iraq, even though a recent Gallup poll shows only 31 percent of respondents think the United States is winning.
"Every time we have a new videotape of bin Laden, it reminds people of the administration's argument that (Iraq) is connected to the war on terror, whether it really is or isn't," said Larry Sabato, a political analyst at the University of Virginia.
"People are conflicted. They think, "I'm not really happy with what's happening in Iraq, but I don't want to do anything to give solace to Osama bin Laden and Zarqawi and al-Qaida.' "
Susan Taylor Martin can be contacted at firstname.lastname@example.org