A great quote on nationalism and exclusion by Jacob Talmon, taken from The Myth of Nation and Vision of Revolution, The Origins of Ideological Polarization in the 20th Century (1981, 1991):

There’s a rhythm in the development of national consciousness. Its first sparks are the feeling of insult and wounded pride experienced by the leaders of the group that is discriminated against from a national or cultural perspective, who had obtained access to the culture of the ruling people but are rejected by it as being inferior. Their feelings deeply hurt, they are driven to search for their roots, to discover the substance and traditions that gave the community from which they emerged the character of a special collective [...] fairly quickly they realize that full, unbridled self-expression includes the necessary condition of political self-determination and thus, political independence.

Very accurate, then.