“Building on Linz’s work, we have developed a set of four behavioral warning signs that can help us know an authoritarian when we see one. We should worry when a politician 1) rejects, in words or action, the democratic rules of the game, 2) denies the legitimacy of opponents, 3) tolerates or encourages violence, or 4) indicates a willingness to curtail the civil liberties of opponents, including the media.”