BAQUBAH, IRAQ — When U.S. forces killed the leader of Al Qaeda in Iraq, Abu Musab Zarqawi, six months ago in a village near here, they hoped security would improve in this strategic province just north of Baghdad.
Instead, security has collapsed in Diyala province, which now ranks as one of Iraq's most troubled regions. Insurgent attacks have more than doubled in the last year. Violence has devastated the provincial police force and brought reconstruction to a virtual standstill.
Assassinations have claimed the lives of mayors, tribal chieftains, police officials and judges, including a Shiite Muslim member of the provincial council who was killed Tuesday. Many government officials here sleep on cots in their offices because driving home is too dangerous.
And Iraqi security forces have been implicated in so many abuses that the U.S. commander here recently gave his Iraqi counterpart an angry lecture, likening the Iraqi troops to an "undisciplined rabble."
U.S. and Iraqi officials interviewed in recent days blamed the sharp downturn on a combination of U.S. neglect and abuses by the Iraqi army. U.S. troops largely disengaged from security here for weeks at a time, they say, handing the reins to Iraqi forces who proved to be abusive and ineffective.
U.S. commanders are attempting a sharp change in strategy, hoping that a classic counterinsurgency campaign, combining reconstruction aid with a more active U.S. presence, can turn the situation around.
For now, insurgents here appear to have gained the upper hand. They demonstrated their freedom of movement last week by barreling a dozen trucks through the streets of Baqubah's Amin neighborhood, shouting militant slogans and brandishing machine guns and shoulder-fired rocket launchers.
The defiant show of force was similar to another insurgent parade caught on video by a U.S. aerial drone in November. Insurgents were seen hauling Shiite families out of their homes and executing them in the streets, U.S. military officials who reviewed the footage said.
Diyala is an area of fertile farmland, abundant water and untapped oil wells stretching north of Baghdad's suburbs and east to the Iranian border. Its population includes all three of Iraq's main religious and ethnic groups.
Of its roughly 1.8 million people, about 55% are Sunni Arabs. But because Sunnis boycotted elections two years ago, Shiites, who make up about one-third of Diyala's population, hold the majority of provincial council seats and control the local security forces. Kurds, mostly in northeastern Diyala, make up about 15%.
Until October, the main U.S. force in the province was the 4th Infantry Division. It largely followed the strategy laid down by top U.S. commanders in Iraq last year: Pull American forces back as much as possible and allow Iraqi troops to take the lead in fighting insurgents. U.S. officers here say that approach did not work.
"4th ID tried to keep a low profile after they handed over security to the Iraqi army, but that approach backfired," said an officer with the 3rd Heavy Brigade Combat Team, 1st Cavalry Division, which now has responsibility for the province. The officer spoke on condition of anonymity because he was criticizing another U.S. military unit.
Under the 4th Infantry's plan, Army convoys stayed on main roads and rarely ventured into Baqubah's dense neighborhoods, military officials said.
"Iraqis told us that 4th ID drove in here with their Humvees and told them, 'If you don't shoot at us, we won't shoot at you,' " the 3rd Brigade officer said. "So the insurgents actually took over this place."
Making matters worse, Iraq's Shiite-dominated government appointed a provincial commander who U.S. military officials say was handpicked by the Badr Brigade, a militia implicated in hundreds of death squad killings in Baghdad. The militia is linked to Iraq's largest Shiite political party, the Supreme Council for Islamic Revolution in Iraq.
Under orders from the Iraqi Ground Forces Command in Baghdad this fall, the commander, Brig. Gen. Shakir Hulail Hussein Kaabi, and his 5th Iraqi Division started a campaign of what U.S. officials now describe as abusive raids and detentions.
The problems were so serious that Col. David W. Sutherland, commander of the 3rd Brigade, took the unusual step of lecturing his Iraqi counterpart during a mid-December briefing at Forward Operating Base Warhorse near Baqubah.
"Six weeks ago, the people of Diyala and Baqubah were disgusted with the disrespect and disregard the Iraqi army had shown them," Sutherland told Shakir through an Arabic interpreter.
"Bullying an innocent person is unacceptable. Taking things from houses is unacceptable. Taking cars or things from cars is unacceptable," he said.
"Before we send an undisciplined rabble into this fight, I will pull the plug," Sutherland told the general. "We are soldiers, not barbarians."