Why UFO files are trending

<p>On Friday, the Pentagon released what it says are “never-before-seen files” on UFOs after President Donald Trump directed the agency to do so earlier this year. CNN’s Tom Foreman explains what some of the files contain and the Pentagon's plans to release more in the future. Discover more videos, including live streams and exclusive storytelling, on our <a href="http://cnn.com/watch">Watch</a> page.</p>