The first troops to leave Afghanistan as part of the U.S. drawdown handed over their slice of battlefield Wednesday to a unit less than half their size and started packing for home. When the 650 members of the Iowa National Guard's 1st Squadron, 113th Cavalry Regiment arrived in Afghanistan in November 2010, bases didn't have enough housing, translators were in short supply and chow halls were packed. Commanders were using a buildup of 33,000 extra troops for a major push that they said would turn the tide of the war against the Taliban insurgency. Nine months later, it's still unclear if that push has succeeded, but the pullback has begun. Although major combat units are not expected to start leaving until late fall, two National Guard regiments comprising about 1,000 soldiers in all are withdrawing this month -- the Iowa soldiers from Parwan province in eastern Afghanistan, and the other group from the capital, Kabul. U.S. soldiers walk into a U.S. military plane, as they leave Afghanistan, at the U.S. base in Bagram, north of Kabul, Afghanistan on Thursday, July 14, 2011. U.S. soldiers with Task Force Red Horse wait in a bus to be transported for the airport section to leave Afghanistan, at the U.S. base in Bagram, north of Kabul, Afghanistan. U.S. soldiers roll up the U.S. flag after a transfer of authority ceremony from Task Force Red Horse to Task Force Maverick at the U.S. base in Bagram, north of Kabul, Afghanistan, on Wednesday, July 13, 2011.