Last February, former President Trump made a deal with the Taliban to withdraw U.S. troops from Afghanistan by May 1st, 2021. After two decades of partnership with the U.S. and its NATO allies, foreign forces are preparing to go home, leaving the Afghan National Security forces to fight the Taliban alone--at a time when peace negotiations with the Taliban have stalled. Special Correspondent Jane Ferguson reports the final installment in the series: "The Longest War." PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders