Stated U.S. policy is to ensure that Afghanistan will not again become a base for terrorist attacks against the United States. Following policy reviews in 2009, the Obama Administration asserted that it was pursuing a well-resourced and integrated military-civilian strategy intended to pave the way for a gradual transition to Afghan leadership from July 2011 until the end of 2014. To carry out U.S. policy, a total of 51,000 additional U.S. forces were authorised by the two 2009 reviews, which brought U.S. troop numbers to a high of about 99,000, with partner forces adding about 42,000. The...