Defense Secretary Leon Panetta (center) walks to his vehicle after being greeted by Ryan Crocker (right), U.S. Ambassador to Afghanistan, and Gen. John Allen upon his arrival in Kabul, Afghanistan on Dec., 13, 2011. (Associated Press)

Photo by: Pablo Martinez Monsivais

Defense Secretary Leon Panetta (center) walks to his vehicle after being greeted by Ryan Crocker (right), U.S. Ambassador to Afghanistan, and Gen. John Allen upon his arrival in Kabul, Afghanistan on Dec., 13, 2011. (Associated Press)