Nationalism must be distinguished from patriotism. Patriotism is fundamental to liberty because pride in one’s nation-state, and a willingness to defend it if necessary, is the basis of national independence. Patriotism is the courage of national self-determination. By contrast, nationalism is patriotism transformed into a sentiment of superiority and aggression toward other countries. Nationalism is the poisonous idea that one’s country is superior to somebody else’s. Nationalism is intrinsically a cause of war and imperialism.