A view of debris left over from temporary housing demolished during work to dismantle vast swaths of the massive Bagram Air Field in the Parwan province of Afghanistan January 2, 2015. Roughly 13,000 foreign troops, mostly Americans, will remain in the country under a new two-year mission named "Resolute Support" to train Afghan troops. REUTERS/Lucas Jackson (AFGHANISTAN - Tags: CIVIL UNREST POLITICS MILITARY)