Around the world, the number of measles cases is on the rise. Public health officials in the United States have put some of the blame on "anti-vaxxers," who believe that vaccines have destructive side effects and choose not to vaccinate their children. In some communities, school systems have made vaccinations mandatory, touching off political battles over personal and religious liberty. Nick Paumgarten joins Dorothy Wickenden to discuss the political lessons of the movement for the wider "war on science."