American forces Sept. 1 handed over security responsibility to the Iraqis in a province that the United States once feared was lost — a sign of the stunning reversal of fortunes since local Sunnis turned against al-Qaida in Iraq.

But a Sunni Arab leader criticized the Shiite-led government of Prime Minister Nouri al-Maliki for failing to embrace its newfound allies, underlining the threat that sectarian tensions still pose to a lasting peace.

Nevertheless, the transfer of Anbar province, the cradle of the Sunni insurgency and the birthplace of al-Qaida in Iraq, marked a milestone in America's plan to eventually hand over all 18 provinces to Iraqi control so U.S. troops can go home.