Secretary of Defense Leon E. Panetta presents Purple Hearts to personnel of the 172nd Infantry Brigade Task Force Blackhawks at a forward operating base in Sharana, Afghanistan, on Wednesday, Dec. 14, 2011. (AP Photo/Pablo Martinez Monsivais, Pool)

Photo by: Pablo Martinez Monsivais

Secretary of Defense Leon E. Panetta presents Purple Hearts to personnel of the 172nd Infantry Brigade Task Force Blackhawks at a forward operating base in Sharana, Afghanistan, on Wednesday, Dec. 14, 2011. (AP Photo/Pablo Martinez Monsivais, Pool)