World History/The Rise of Nationalism and the Nation-state

What is Nationalism?
Nationalism is a belief, creed or political ideology that involves an individual identifying with, or becoming attached to, one's nation. Nationalism involves national identity, by contrast with the related construct of patriotism, which involves the social conditioning and personal behaviors that support a state's decisions and actions.

Perspectives
From a psychological perspective, nationalism (national attachment) is distinct from other types of attachment, for example, attachment to a religion or a romantic partner. The desire for interpersonal attachment, or the need to belong, is one of the most fundamental human motivations. Like any attachment, nationalism can become dysfunctional if excessively applied.

From a political or sociological perspective, there are two main perspectives on the origins and basis of nationalism. One is the primordialist perspective that describes nationalism as a reflection of the ancient and perceived evolutionary tendency of humans to organize into distinct groupings based on an affinity of birth. The other is the modernist perspective that describes nationalism as a recent phenomenon that requires the structural conditions of modern society in order to exist.

What is a nation state?
There are various definitions for what constitutes a nation, however, which leads to several different strands of nationalism. It can be a belief that citizenship in a state should be limited to one ethnic, cultural, religious, or identity group, or that multinationality in a single state should necessarily comprise the right to express and exercise national identity even by minorities. The adoption of national identity in terms of historical development has commonly been the result of a response by influential groups unsatisfied with traditional identities due to inconsistency between their defined social order and the experience of that social order by its members, resulting in a situation of anomie that nationalists seek to resolve. This anomie results in a society or societies reinterpreting identity, retaining elements that are deemed acceptable and removing elements deemed unacceptable, in order to create a unified community. This development may be the result of internal structural issues or the result of resentment by an existing group or groups towards other communities, especially foreign powers that are or are deemed to be controlling them. National flags, national anthems and other symbols of national identity are commonly considered highly important symbols of the national community.

The nation state is a state that self-identifies as deriving its political legitimacy from serving as a sovereign entity for a nation as a sovereign territorial unit. The state is a political and geopolitical entity, while the nation is a cultural and/or ethnic one; the term "nation state" implies that the two coincide geographically. Nation state formation took place at different times in different parts of the world, but has become the dominant form of state organization.

The concept and actuality of the nation state can be compared and contrasted with that of the multinational state, city state, empire, confederation, and other state forms with which it may overlap. The key distinction from the other forms is the identification of a people with a polity.