Although the term “nationalism” has a variety of meanings, it centrally encompasses the two phenomena noted at the outset: (1) the attitude that the members of a nation have when they care about their identity as members of that nation and (2) the actions that the members of a nation take in seeking to achieve (or sustain) some form of political sovereignty (see for example, Nielsen 1998–9, 9). Each of these aspects requires elaboration. (1) raises questions about the concept of a nation or national identity, about what it is to belong to a nation, and about how much one ought to care about one's nation. Nations and national identity may be defined in terms of common origin, ethnicity, or cultural ties, and while an individual's membership in the nation is often regarded as involuntary, it is sometimes regarded as voluntary. The degree of care for one's nation that nationalists require is often, but not always, taken to be very high: according to such views, the claims of one's nation take precedence over rival contenders for authority and loyalty (see Berlin 1979, Smith 1991, Levy 2000, and the discussion in Gans 2003; for a more extreme characterization see the opening pages of Crosby 2005, and for a recent rich and interesting discussions of nationalist attitudes see Yack 2012).
(2) raises questions about whether sovereignty requires the acquisition of full statehood with complete authority over domestic and international affairs, or whether something less than statehood suffices. Although sovereignty is often taken to mean full statehood (Gellner 1983, ch. 1; for discussion of Gellner's views see Meadwell 2012, 2014, and papers in Malesevic and Hugarard 2007), possible exceptions have been recognized (Miller 1992 (87), and Miller 2000). Some authors even defend an anarchist version of patriotism-moderate nationalism foreshadowed by Bakunin (see Robert Sparrow, “For the Union Makes Us Strong: Anarchism and Patriotism”, in Primoratz and Pavkovic 2007).
Despite these definitional worries, there is a fair amount of agreement about the historically paradigmatic form of nationalism. It typically features the supremacy of the nation's claims over other claims to individual allegiance and full sovereignty as the persistent aim of its political program. Territorial sovereignty has traditionally been seen as a defining element of state power and essential for nationhood. It was extolled in classic modern works by Hobbes, Locke, and Rousseau and is returning to center stage in the debate, though philosophers are now more skeptical (see below). Issues surrounding the control of the movement of money and people (in particular immigration) and the resource rights implied in territorial sovereignty make the topic politically center in the age of globalization and philosophically interesting for nationalists and anti-nationalists alike.
The territorial state as political unit is seen by nationalists as centrally ‘belonging’ to one ethnic-cultural group and as actively charged with protecting and promulgating its traditions. This view is exemplified by the classical, “revivalist” nationalism that was most prominent in the 19th century in Europe and Latin America. This classical nationalism later spread across the world and still marks many contemporary nationalisms.