This article is just so full of good, pithy pullquotes: "Those hoping to make positive social change have to convince people both that something in the world needs changing and there is a constructive, reasonable way to change it. Authoritarians and extremists, on the other hand, often merely have to muddy the waters and weaken trust in general so that everyone is too fractured and paralyzed to act." https://www.technologyreview.com/s/611806/how-social-media-took-us-from-tahrir-square-to-donald-trump/