Nation-states today are under pressure from opposite directions. In Western Europe, they are being challenged by the call of assimilation into a larger supra-national polity. Elsewhere, as in Southeastern Europe, nation-states are being challenged by separatist forces from within, demanding independence or self-determination for particular ethnic groups. In either instance, the ultimate aim is not simply the breaking of bonds but rather a realignment of belonging.

When the prospect of prosperity and the good life requires an adjustment of national identities and alliances, old myths...