The Iraq insurgency of 2004-2007 was responded to with a troop surge that increased the US military presence in Iraq that "drastically reduced violence and helped the Iraqi government take control of about half the country's 18 provinces." 
In late 2007 President George W. Bush removed Defense Secretary Donald Rumsfeld and tried the warfighting strategy proposed by General David Petraeus, who was given additional forces. Petraeus sent in 30,000 additional combat troops under Lt. Gen. Ray Odierno, who contained the insurgency and cleared the enemy out of the belts surrounding Baghdad. Sunni leaders and tribal chiefs, fed up with al Qaeda atrocities, set up militias in tactical alliance with coalition and Iraqi government forces, The long ceasefire of Moqtada al Sadr's Shia extremists helped to reduce sectarian tension. Within a few months, Baghdad had been transformed: attacks were down by 60%, civilian deaths had dropped 70% and sectarian attacks of one sort and other had fallen by a staggering 90%. The success of "The Surge" strategy made possible the achievement of Bush's timetable for the withdrawal of American troops from Iraq's major cities in summer 2009.
Battle of Tal Afar
In 2005 Col. H.R. McMaster took responsibility for Tal Afar, a city which at one time was populated by 200,000 people, but had fallen to 80,000 during the insurgency. When McMaster and the 3d Armored Cavalry Regiment arrived in the spring of 2005, the city was largely in the hands of hard-core foreign jihadis who, together with local jihadis, had destabilized the city with a campaign of intimidation, including beheadings aimed largely at Tal Afar’s Shiite minority.
The city's mayor reported in 2006 the “savagery reached such a level that they stuffed the corpses of children with explosives and tossed them into the streets in order to kill grieving parents attempting to retrieve the bodies of their young. This was the situation of our city until God prepared and delivered unto them the courageous soldiers of the 3d Armored Cavalry Regiment.”
McMaster’s troops fought in Tal Afar with the understanding that victory would not be achieved by using maximum violence to hunt and kill insurgents. Instead, the key tasks were to secure and improve life for the local population, establish reliable local government, and project determination and staying power.
- Kimberly Kagan, The Surge: A Military History (2009)