Nationalism has played an enormous role in world history over the past few hundred years. It continues to do so. For many—I suspect for most who open this book—it is indelibly associated with some of the worst aspects of modern history. Large numbers of otherwise decent people have carried out unbelievable atrocities for no better reason than their nation required them to. Authoritarian and totalitarian regimes have crushed dissent, eliminated opposition and trampled on civil liberties in the name of the nation. The rhetoric of national identity is used to stand in the way of civilised policies towards refugees and immigrants. Yet, as we recount the horrors, we should also be—perhaps uncomfortably—aware how much we take the nation for granted in our day to day life. Without thinking about it, we pick out one stretch of territory and one collection of historical narratives as ours, and we recognise one group of people as fellow members of our nation. And even the horrors have another side. Nations have called forth heroism and sacrifice as well as murder and torture. People have risked their lives to restore democracy and civil rights in their own country, when they could easily have chosen comfortable exile elsewhere. Programmes of health reform, social welfare and environmental repair have gained political support because they appeal to a sense of national identity.
Nationalism has always been of interest to historians and social theorists. In the eighteenth and nineteenth centuries, it also received considerable attention from philosophers. But for most of the twentieth century, it has been all but ignored by philosophers. Students of moral and political philosophy might attend lectures, read the recommended texts and complete their degrees without coming across the concepts of the nation, national identity and nationalism. The overwhelming consensus among philosophers was that nationalism was not worth talking about. For example, Robert E. Goodin and