It has been 16 months since the United States left Afghanistan in what a top U.S. military officer called a “strategic defeat.” The new film "Retrograde" documents the withdrawal, the Afghan forces left to fight on their own, and the chaotic conclusion to 20 years of war. Nick Schifrin sat down with filmmaker Matthew Heineman and one of his central characters. Stream your PBS favorites with the PBS app: to.pbs.org/2Jb8twG Find more from PBS NewsHour at www.pbs.org/newshour Subscribe to our YouTube channel: bit.ly/2HfsCD6 Follow us: TikTok: www.tiktok.com/@pbsnews Twitter: www.twitter.com/newshour Instagram: www.instagram.com/newshour Facebook: www.pbs.org/newshour Subscribe: PBS NewsHour podcasts: www.pbs.org/newshour/podcasts Newsletters: www.pbs.org/newshour/subscribe