The following is the Feb. 26, 2019 Congressional Research Service report, Afghanistan: Background and U.S. Policy In Brief.
From the report
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 it. In the intervening 17 years, the United States has suffered around 2,400 fatalities in Afghanistan (including 2 in 2019 to date) and Congress has appropriated more than $132 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. The fundamental objective of U.S. efforts in Afghanistan is “preventing any further attacks on the United States by terrorists enjoying safe haven or support in Afghanistan.”
In early 2019, U.S. military engagement in Afghanistan appears closer to ending than perhaps ever before as U.S. officials negotiate directly with Taliban interlocutors on the issues of counterterrorism and the presence of U.S. troops. However, U.S. negotiators caution that talks are still at a preliminary stage, and Afghan government representatives have not been directly involved. Lead U.S. negotiator Zalmay Khalilzad insists that the U.S. seeks a comprehensive peace agreement but some worry that the U.S. will prioritize a military withdrawal over a complex political settlement that preserves some of the social, political, and humanitarian gains made since 2001. It remains unclear what kind of political arrangement could satisfy both Kabul and the Taliban to the extent that the latter fully abandons armed struggle.
Press reports in December 2018 and early 2019 indicate that the Trump Administration may be considering withdrawing some U.S. forces, though U.S. officials maintain that no policy decision has been made to reduce
U.S. force levels. Many observers assess that a full-scale U.S. withdrawal would lead to the collapse of the Afghan government and perhaps even the reestablishment of Taliban control over the entire country; by many measures, the Taliban are in a stronger military position now than at any point since 2001. Underlying the negotiations is the unsettled state of Afghan politics, which is a major complicating factor: Afghanistan held inconclusive parliamentary elections in October 2018 and the all-important presidential election, originally scheduled for April 2019, has been postponed until July 2019.
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