"The United States and its partner countries are gradually reducing military involvement in Afghanistan as the end of the formal international security mission approaches by the end of 2014. Under an agreement between President Obama and Afghan President Karzai announced January 11, 2013, Afghan forces will assume the security lead nationwide in the spring of 2013 and U.S. forces will move to a support role. The number of U.S. forces in Afghanistan, which peaked at about 100,000 in June 2011, has been reduced to a 'pre-surge' level of 66,000 as of September 20, 2012, and a further draw down schedule is to be announced by mid-2013. Subsequently, the size of the U.S. force that will remain in Afghanistan after 2014 will be announced, pursuant to a bilateral security agreement between the United States and Afghanistan that is under negotiation pursuant to a May 1, 2012, U.S.-Afghan Strategic Partnership Agreement. U.S. military recommendations for the post-2014 force reportedly range from 3,000 to 20,000 U.S. forces, likely performing missions that include combat against high-value targets as well as training for the Afghanistan National Security Forces (ANSF). U.S. partners are likely to contribute a still unspecified number of forces for these missions. Still, fearing instability after 2014, some key ethnic and political faction leaders are preparing to revive their militia forces should the international drawdown lead to a major Taliban push to retake power."
CRS Report for Congress, RL30588