This thoughtful essay by a leading public intellectual asks one of the great questions of our time: How can Western societies remain faithful to liberal values of openness and freedom when defeating terrorism often requires secrecy and coercion? Ignatieff responds by offering a set of principles by which liberal democracies can navigate between the competing moral imperatives of protecting individual rights and protecting the community. In his ethical rendering, neither security nor liberalism holds a trump card; governments may indeed need to violate rights in a terrorist emergency, but it should be done with a "conservative bias" -- with due process, adversarial proceedings, and other legal safeguards. Ignatieff also acknowledges that societies can make prudent tradeoffs only if they can accurately assess the magnitude of the threat -- a historically difficult task when the threat is a shadowy terrorist network. Surveying the long history of terrorist violence in democratic societies, Ignatieff concludes that liberal states consistently overreact and too readily curtail freedoms. He ends by eloquently arguing that a liberal democracy can survive the age of terror only if it takes seriously the political context within which terrorism thrives -- that is, by engaging, persuading, and championing social justice.