Milestones of the Iraq War -- PICTURES

Mar. 20, 2003: The Iraq War began at 5:34 a.m. Baghdad time, as military forces led by Gen. Tommy Franks worked with coalition forces to invade the country. In the photo above, a government building burns during heavy bombardment of Baghdad. (JEROME DELAY/AP)

Early April, 2003: Less than a month after the invasion began, coalition forces led by the U.S. Army 3rd Division moved into Baghdad. In this photo, U.S. helicopters overfly the area as workers dismantle one of the four giant bronze busts of Saddam Hussein that long dominated Baghdad's skyline. (ANJA NIEDRINGHAUS/AP)

May 1, 2003: President Bush declared the end of major combat in Iraq while aboard the aircraft carrier USS Abraham Lincoln. The "Mission Accomplished" banner behind Bush in the photo became infamous as the Iraq War dragged through the rest of the decade. (J. SCOTT APPLEWHITE/AP)

Dec. 13, 2003: In the months after the fall of Baghdad, Saddam Hussein managed to evade capture. U.S. forces found him in Ad Dawr, a small town near Tikrit, in what was reported as a "spiderhole." Hussein would be found guilty of crimes against humanity in November 2006 and executed on Dec. 30 of that year. (WIKIMEDIA COMMONS)

2004: The Baghdad Correctional Facility, also known as Abu Ghraib, came under fire beginning in 2004 for human rights violations that included physical and psychological torture of prisoners. Eleven military personnel were convicted by courts-martial in connection with the abuse. (AP PHOTO)

Jan. 31, 2005: Residents of Baghdad's Shiite enclave celebrate on the street waving with flowers, flags and posters a day after Iraqis went to the polls to elect a transitional government. (KARIM KADIM/AP)

Early 2007: President Bush used his 2007 State of the Union address to announce "reinforcements of more than 20,000 additional soliders and Marines to Iraq." The "surge," as it came to be known, was a brainchild of Gen. David Petraeus, who was confirmed as the commander of Multinational Force - Iraq in February. By March 2008, violence in Iraq had fallen by at least 40 percent, according to a Pentagon report. (DENNIS COOK/AP)

Aug. 31, 2010: In an address from the Oval Office, President Obama formally announced the end of Operation Iraqi Freedom and the start of a significant troop drawdown. (PABLO MARTINEZ MONSIVAIS/AP, POOL)

Dec. 15, 2011: The day after President Obama spoke to troops at Fort Bragg, N.C., the Iraq war officially ended. The war lasted more than eight years and cost 4,497 American lives. (CAROLYN KASTER/AP)