"Operation Iraqi Freedom overthrew Saddam Hussein's regime, but Iraq remains unstable because of Sunni Arab resentment and a related insurgency, compounded by Sunni-Shiite violence that a January 2007 national intelligence estimate says has key elements of a "civil war." Mounting U.S. casualties and financial costs - without clear signs of security progress - have intensified a debate within the United States over whether to wind down U.S. involvement without completely accomplishing initial U.S. goals. U.S. Defense Department reports, the December 6, 2006, report of the Iraq Study Group, and the national intelligence estimate referenced above express pessimism about security in Iraq. Bush Administration officials are expressing some frustration at the unwillingness of the Iraqi government to disband sectarian militias that are committing violence against civilians of rival sects. In an effort to counter these trends, President Bush addressed the nation on new initiatives in Iraq on January 10, 2007 and announced a deployment of an additional 21,500 U.S. forces to help stabilize Baghdad and restive Anbar Province, as well as other measures to create jobs and promote political reconciliation. He and other officials have previously asserted that U.S. policy has shown some important successes: two elections (January and December 2005) that chose an interim and then a full-term parliament and government; a referendum that adopted a permanent constitution (October 15, 2005); progress in building Iraq's security forces; and economic growth. While continuing to build, equip, and train Iraqi security units, the Administration has worked to include more Sunni Arabs in the power structure, particularly the security institutions."
CRS Report for Congress, RL31339