Abstract: What is the constitutional status of falsehoods? From the standpoint of the First Amendment, does truth or falsity matter? These questions have become especially pressing with the increasing power of social media, the frequent contestation of established facts, and the current focus on “fake news,” disseminated by both foreign and domestic agents in an effort to drive U.S. politics in particular directions. In 2012, the Supreme Court ruled for the first time that intentional falsehoods are protected by the First Amendment, at least when they do not cause serious harm. But in important ways, 2012 seems like a generation ago, and the Court has yet to give an adequate explanation for its conclusion. Such an explanation must begin the risk of a “chilling effect,” by which an effort to punish or deter falsehoods might also and in the process chill truth. But that is hardly the only reason to protect falsehoods, intentional or otherwise; there are several others. Even so, these arguments suffer from abstraction and high-mindedness; they do not amount to decisive reasons to protect falsehoods. These propositions are applied to old questions involving defamation and to new questions involving fake news, deepfakes, and doctored videos. It emerges that New York Times v. Sullivan is an anachronism, and that it should be rethought in light of current technologies and new findings in behavioral science. Government should have authority to control deepfakes and doctored videos, and also certain kinds of “fake news,” when it threatens political processes. It also emerges that Facebook, Twitter, and other social media platforms should do far more than they are now doing to control falsehoods, deepfakes, and doctored videos.