“Nationalism,” writes Arthur N. Waldron, “in general is a powerful and comprehensible idea. Yet while it defines general situations, it is not very useful in explicating specific events” (1985: 427). The “adjective ‘nationalist’ has been attached to people, movements, and sentiments in a way that is usually taken (without explanation) as distinguishing each of them meaningfully from some other variety.” Waldron's analytical stance suffices so long as we take no interest in the dynamics of nationalism or in its interaction with other forms of public politics. Nationalism is part of struggle – contentious politics, in our lexicon. As we have argued repeatedly, we cannot understand any episode of contentious politics as the expression of any single discourse, ideology, or nominally distinct form of contention.

To understand why nationalism arises, we must understand its varied political sources. We need to know when and why they sometimes converge in nationalist outcomes. We must also ask to what extent nationalist episodes are the result of structural factors, institutional constraints, and cultural constants, and to what extent they emerge from cascades of contention. When we do so, we are likely to find that nationalist outcomes intersect with motives, movements, and state policies having little to do with nationalism. We are thus likely to find similar mechanisms to those that drive other forms of contention. As a corollary, we should discover that similar mechanisms underlie what history has coded as contrary nationalist processes – such as national disintegration and nation-state building.