U.S. President Barack Obama walks with USAF Col. Mark Camerer, 436th Airlift Wing Commander, after he arrives at Dover Air Force Base in Delaware, August 9, 2011. Obama flew to a Delaware air force base on Tuesday to honor the return of the remains of 30 U.S. troops killed when Taliban insurgents shot down their helicopter in Afghanistan. REUTERS/Larry Downing (UNITED STATES – Tags: POLITICS)