ABSTRACT
US forces entered Iraq on 19 March 2003 in an invasion dubbed Operation Iraqi Freedom (OIF) in order to overthrow the regime of Iraqi leader, Saddam Hussein, who was viewed as a recalcitrant and irredeemable tyrannical ruler. By the end of the year Iraq was in the throes of a full-scale insurgency by a section of its population, the Sunnis, against the Coalition presence. Irregular warfare was something that the superb conventional US military neither expected nor knew how to deal with. Lacking effective doctrine for countering insurgencies, the United States flailed around and became frustrated; its early failures contributed to fanning the flames of anger and humiliation (see Burton and Nagl 2008: 303–27; Sepp 2007: 217–30). The fighting was so extensive and bitter that between 2003 and 2005 it has produced nearly ten times as many Coalition casualties as the fight to topple the regime and defeat Iraq's army. After 2006 the insurgency evolved into a bitter civil war between Sunnis and Shiites that has only gradually been brought under control in the last two years. The purpose of this chapter is to address the origins/causes, ideologies, goals and evolution of the insurgency after 2003 and assess the factors behind its failures and ultimate decline.
