Thousands of documents related to the 1963 assassination of President John F. Kennedy have been declassified, but thousands more will remain secret despite a law that called for them to be unsealed five years ago. NBC News’ Monica Alba and presidential historian Michael Beschloss break down what documents are being released and why the government may have held some back from the public.  » Subscribe to NBC News: http://nbcnews.to/SubscribeToNBC » Watch more NBC video: http://bit.ly/MoreNBCNews NBC News Digital is a collection of innovative and powerful news brands that deliver compelling, diverse and engaging news stories. NBC News Digital features NBCNews.com, MSNBC.com, TODAY.com, Nightly News, Meet the Press, Dateline, and the existing apps and digital extensions of these respective properties. We deliver the best in breaking news, live video coverage, original journalism and segments from your favorite NBC News Shows. Connect with NBC News Online! NBC News App: https://smart.link/5d0cd9df61b80 Breaking News Alerts: https://link.nbcnews.com/join/5cj/breaking-news-signup?cid=sm_npd_nn_yt_bn-clip_190621 Visit NBCNews.Com: http://nbcnews.to/ReadNBC Find NBC News on Facebook: http://nbcnews.to/LikeNBC Follow NBC News on Twitter: http://nbcnews.to/FollowNBC #JFK #JohnFKennedy #Assassination