Though not for the squeamish, every American adult ought to watch Taxi to the Dark Side (2007). I also recommend watching 2010's documentary, The Oath, before watching Taxi to the Dark Side.
Both documentaries present mostly unfiltered information from first-hand sources, including frontline military personnel and former Al Qaeda members, about Guantanamo Bay, Iraq, Afghanistan, Al-Qaeda, and Abu Ghraib.
Update on 6/24/13: more movie recommendations here: http://willworkforjustice.blogspot.com/2009/08/best-non-famous-movies.html
Update on August 31, 2015: Check out Dirty Wars (2013).
Both documentaries present mostly unfiltered information from first-hand sources, including frontline military personnel and former Al Qaeda members, about Guantanamo Bay, Iraq, Afghanistan, Al-Qaeda, and Abu Ghraib.
Update on 6/24/13: more movie recommendations here: http://willworkforjustice.blogspot.com/2009/08/best-non-famous-movies.html
Update on August 31, 2015: Check out Dirty Wars (2013).