The New York Times reports: Meeting various neighbors and supplicants on a recent evening, America’s staunchest ally in Iraq, Sheik Ahmed Abu Risha, sat in a tent sipping tea from an implausibly tiny glass cup. He greeted each new visitor with a hearty outburst of “dear one” and a kiss on the cheek.

At one point a young man walked in carrying an M-16 rifle, leaned over and kissed the sheik on the cheek, too, in a clear sign of loyalty from a member of a tribal militia.

Mr. Abu Risha is often credited with helping turn the tide of the Iraq war beginning in 2006 by rallying local tribal leaders to fight Al Qaeda in Mesopotamia, the homegrown Qaeda affiliate in Iraq, which has some foreign members. He still commands, by his own estimate, about 80,000 militia members.

With two weeks left before the United States military completes its withdrawal from Iraq, these units, known broadly as the Sunni Awakening, still remain outside the new Iraqi police force and army. Ragtag groups of men wearing jeans and carrying rifles at dusty checkpoints throughout western Iraq, they are a loose end left by the United States.

Some Awakening members are former insurgents and members of Saddam Hussein’s Baath Party who fought in a nationalist wing of the Sunni uprising early in the war, a matter of grave concern to the Shiite-dominated government of Prime Minister Nuri Kamal al-Maliki. Without the buffer provided by the Americans, relations between the Awakening and the central government, always touchy, are growing increasingly strained, and the government now wants the Awakening to disband by Dec. 31, the deadline for the exit of the United States military.

Mr. Abu Risha, in an interview in his compound beside a lazy bend in the Euphrates River, said members of the tribal militias in western Iraq were not likely to disarm quickly — and certainly not by the end of the month.