Backlash against foreign fighters in Iraq?

Christopher Hitchens wonders if it is Curtains for al-Qaida. The article quotes the following from a Washington Post report - Rising up against insurgent leader Abu Musab Zarqawi, Iraqi Sunni Muslims in Ramadi fought with grenade launchers and automatic weapons Saturday to defend their Shiite neighbors against a bid to drive them from the western city. … Dozens of Sunni members of the Dulaimi tribe established cordons around Shiite homes, and Sunni men battled followers of Zarqawi, a Jordanian, for an hour Saturday morning. The clashes killed five of Zarqawi's guerrillas and two tribal fighters, residents and hospital workers said. Zarqawi loyalists pulled out of two contested neighborhoods in pickup trucks stripped of license plates, witnesses said.