"Afghanistan has been a central U.S. foreign policy concern since 2001, when the United States, in response to the terrorist attacks of September 11, 2001, led a military campaign against Al Qaeda and the Taliban government that harbored and supported Al Qaeda. In the intervening 16 years, the United States has suffered more than 2,000 casualties in Afghanistan (including 14 in 2017) and has spent more than $120 billion for reconstruction there. In that time, an elected Afghan government has replaced the Taliban, and nearly every measure of human development has improved, although future prospects of those measures remain mixed. U.S. policymakers routinely describe the war against the insurgency (which controls or contests nearly half of the country's territory, by Pentagon estimates) as a 'stalemate' and the Afghan government faces broad public criticism for its ongoing inability to combat corruption, deliver security, alleviate rising ethnic tensions, and develop the economy. The total number of U.S. troops in the country is reported as around 15,000, with the deployment of another 1,000 troops reportedly under consideration. This report provides an overview of current political and military dynamics, with a focus on the Trump Administration's new strategy for Afghanistan and South Asia, the U.S.-led coalition and Afghan military operations, and recent political developments, including prospects for peace talks and elections."
CRS Report for Congress, R45122