The debate between privacy and national security has never been more heated, with Apple and other tech firms going up against the government. So how are text messages encrypted, and what are the controversial "backdoors" that could allow access to them? Subscribe to the WSJ channel here: http://bit.ly/14Q81Xy More from the Wall Street Journal: Visit WSJ.com: http://www.wsj.com/ Follow WSJ on Facebook: http://www.facebook.com/wsjvideo Follow WSJ on Google+: https://plus.google.com/+wsj/posts Follow WSJ on Twitter: https://twitter.com/WSJvideo Follow WSJ on Instagram: http://instagram.com/wsj Follow WSJ on Pinterest: http://www.pinterest.com/wsj/ Don’t miss a WSJ video, subscribe here: http://bit.ly/14Q81Xy More from the Wall Street Journal: Visit WSJ.com: http://www.wsj.com/ Visit the WSJ Video Center: https://wsj.com/video On Facebook: https://www.facebook.com/pg/wsj/videos/ On Twitter: https://twitter.com/WSJ On Snapchat: https://on.wsj.com/2ratjSM