Members of the United States Air Force from the 447 Expeditionary Logistics Readiness Squadron (ELRS), one of the last units to leave Baghdad, arrive at U.S. Air Force base Ali Al Salem near Kuwait City December 17, 2011. American soldiers signed over their last military base to Iraqi officials on Friday with the U.S. troop pullout drawing to a swift end nearly nine years after the invasion that ousted Saddam Hussein. REUTERS/Shannon Stapleton (KUWAIT - Tags: MILITARY POLITICS)