The book explores the many reasons why nationalism still matters and the dangers posed by an overly hasty attempt to turn post national ideals into political practice. Nationalism matters, in the first place, because of the ways in which it facilitates social solidarity. Though strong nationalism is hardly a guarantee of democracy, nationalism has nonetheless been integral to the social and cultural transformations that have produced democracy. When considering what a postnational world might look like it is vital to remember that democracy has most often been achieved, however imperfectly, in nation-state structures - and that the dominant institutions of actually existing globalization offer little accountability, let alone democracy. Nationalism matters secondly, because accelerating globalization calls for a search for units of collective organization through which to locate individual existence and facilitate not only political but personal balances of belonging and autonomy. Nationalism is not really opposed to internationalism, thus, it is a way of organizing it. And national identities matter not only in organizing international relations but (alongside religion, region, and ethnicity) in organizing translational flows from migrations to circuits of global exchange. Third, nationalism matters because nations are among the most important and sometimes effective solidarities through which citizens resist versions of globalization that bring freedom to the powerful but challenges without comparable new resources to many others. Neoliberalism's pursuit of unrestricted global markets brings destruction of social institutions built at a national level through generations of struggle. The book ends with an effort to reveal why nationalism still matters, why its complex interrelationships with ethnicity will remain on the social science agenda, and why a stronger internationalism may be more helpful than the assumption that nationalism can easily be transcended.