Nearly nine years after American troops stormed across the Iraq border in a blaze of shock and awe, U.S. officials quietly ended the bloody and bitterly divisive conflict Thursday in a 45-minute simple ceremony held on the edge of Baghdad's international airport. "To be sure the cost was high - in blood and treasure of the United States and also the Iraqi people," Defense Secretary Leon Panetta told the roughly 200 troops and others in attendance. "Those lives have not been lost in vain -- they gave birth to an independent, free and sovereign Iraq." The speeches touched on the success of the mission as well as its losses: Nearly 4,500 Americans and 100,000 Iraqis killed. Another 32,000 American and tens of thousands Iraqis wounded. And $800 billion from the U.S. Treasury.