Justifying exclusion: Political membership and the nation-state

All nation-states claim the right to impose and enforce limitations on political membership. They patrol their borders, set quotas on immigration, and impose requirements for the naturalization of foreign-born residents. From a legal point of view, these practices are just one of many aspects of state sovereignty. But it is doubtful that a state's moral right to regulate admission and citizenship is absolute.;Standard approaches to the ethics of immigration argue for a right to restrict immigration from territorial rights, from the value of national communities, or from the limited scope of liberal justice. This dissertation shows how these approaches fail, and suggests that we pay more attention to assessing the consequences of migration from the perspective of global justice.;Chapter 1 frames the argument by distinguishing different levels of exclusion (exclusion from territory, from residency, and from citizenship) and showing that the morally salient aspect in all of these is the exclusion from the benefits of permanent residence and political representation. Chapter 2 considers a justification for exclusion based upon the Lockean conception of territory rights, and shows how this justification fails under real-world circumstances of vast inequality, oppression, and a history of violence and colonialism. Chapter 3 argues that liberal accounts of nationalist arguments for exclusion---which emphasize the value of national identity and culture---offer an inconsistent view of the good exclusion is supposed to protect. Chapter 4 examines liberal arguments for exclusion from the necessity of protecting liberal institutions and from the limited scope of justice. It argues that exclusion is not necessary for the former and that the scope of justice is global. In other words, nation-states have extensive obligations to outsiders.;Chapter 5 considers the question whether these obligations require affluent states to accept more immigrants from poorer countries. It considers the potential harms and benefits for the migrants, the sending countries, and the receiving countries, and suggests the following measures for minimizing the harms and maximizing the benefits under current, non-ideal circumstances: better protection of migrant workers, long-term investment of remittances, abolishing the distinction between "economic" and "genuine" refugees.