After nearly nine years, 4,500 American dead, 32,000 wounded and more than $800 billion, U.S. officials formally shut down the war in Iraq—a conflict that U.S. Defense Secretary Leon Panetta said was worth the price in blood and money, as it set Iraq on a path to democracy.

Panetta stepped off his military plane in Baghdad Thursday as the leader of America's war in Iraq, but will leave as one of many top U.S. and global officials who hope to work with the struggling nation as it tries to find its new place in the Middle East and the broader world.

More than 100,000 Iraqis have been killed since the U.S. invasion in 2003, according to the Iraq Body Count website. Bombings and gun battles are still common.