The Hawai'i Marines faced insurgents, al-Qaida influence, internecine tribal warfare and a population disenfranchised from the central Iraq government.

Among their solutions to provide incrementally better security was the construction of about 20 miles of berms around three Euphrates River towns and a vehicle registration effort to keep out cars with bombs, mortars and fighters.

About 900 Marines with the 2nd Battalion, 3rd Marine Regiment are leaving western Iraq after seven months. They were part of what has become ongoing Hawai'i rotations to the "Triad" region of Haditha, Haqlaniyah and Barwana, and another 900 Kane'ohe Bay Marines from the 1st Battalion, 3rd Marines just took over.

More than 600 artillery Marines from Kane'ohe also are deploying to Iraq to serve as military police.

Lt. Col. Jim Donnellan, the outgoing battalion commander for the nearly 1,000-square-miles of western Iraq, yesterday said a widely respected mayor and police chief are in place, tribal sheiks are rebelling against insurgents, and attacks on Marines are down with the barriers to outside vehicles.

"I think from this point forward, there's certainly the potential to go up exponentially (with security) as opposed to incrementally," Donnellan said from Iraq.

Haditha is in Anbar province, which is the heartland of resistance to U.S. efforts. The 2/3 Marines lost 23 from their ranks to roadside bombs, snipers and small arms.

Donnellan provided the mission wrap-up by phone as his Marines prepare to return home. Flights are moving the unit to Kuwait, and he said the entire battalion should be back in Hawai'i within seven to 10 days.

Each region of Iraq has its own dynamic in the larger war, and Donnellan admits the progress that's been made is precarious.

One sheik he worked with was murdered, and a favorite tactic by insurgents is to intimidate those who cooperate with American rebuilding efforts.

"It can be a huge tipping point, and we can have schools and roads and electricity ... or it can stagnate if they get to the wrong guy," he said.

"The enemy will absolutely try to undercut any progress" that the mayor and police chief make, and both are on insurgents' hit lists, the battalion commander said.

One of the strongest messages passed on to the replacement 1/3 Marines is the need to protect both.

"And then they've got to to identify projects that we can start getting some progress rolling on, and the mayor can be seen as a guy who makes things happen," Donnellan said.

Four years after the Iraq war started, Anbar remains a serious challenge. Snipers in particular gained in proficiency, and were responsible for a number of 2/3 Marine deaths.

But a growing number of Sunni tribesmen have turned against al-Qaida-linked insurgents in Anbar, and the shift in alliances has reduced what were daily street battles, officials say.

Insurgents have killed at least four sheiks for cooperating with the Americans, but Sunnis are becoming fed up with brutal al-Qaida tactics.

Insurgents killed a prominent sheik last year and refused to let family members bury the body for four days, enraging Sunni tribesmen, according to the U.S. military.

Prior to December, the Hawai'i Marines instituted vehicle restrictions in 30,000-population Haditha, starting with a short-term ban on all traffic. Donnellan said because "it is such a vehicle-borne insurgency, the attacks just dried up."

That was followed by operation "al Majid" to build earthen berms around Triad cities to limit traffic entry. Vehicle registrations and passes also were instituted.

Residents don't like the restrictions but realize that they've improved security and have asked the Marines to be very deliberate about who can drive around town, Donnellan said.

As a result, attacks against Marines are down.

"In October, we were around 12 a day," Donnellan said. "Now it's like one or two a day."

Reach William Cole at wcole@honoluluadvertiser.com.