Causes
There are two major bodies of thought on the causes of nationalism, one is the modernist perspective that describes nationalism as a recent phenomenon that requires the structural conditions of modern society, in order to exist; the other is the primordialist perspective that describes nationalism as a reflection of the ancient and perceived evolutionary tendency of humans to organize into distinct grouping based on an affinity of birth. Roger Masters in The Nature of Politics (Yale University Press, 1991) says that the primordialist and modernist conceptions of nationalism both involve an acceptance of three levels of common interest of individuals or groups in national identity. The first level is that at an inter-group level, humans respond to competition or conflict by organizing into groups to either attack other groups or defend their group from hostile groups. The second level is the intragroup level, individuals gain advantage through cooperation with others in securing collective goods that are not accessible through individual effort alone. The third level is the individual level, where self-interested concerns over personal fitness by individuals either consciously or subconsciously motivate the creation of group formation as a means of security. Leadership groups' or elites' behaviour that involves efforts to advance their own fitness when they are involved in the mobilization of an ethnic or national group is crucial in the development of the culture of that group.
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