Defining Nationalist Extremism

Every fool who has nothing at all of which he can be proud, adopts as a last resource pride in the nation to which he belongs; he is ready and happy to defend all it's faults and follies tooth and nail, thus reimbursing himself for his own inferiority.
 -- Arthur Schopenhauer

(Arthur Schopenhauer (1788-1860) was a German philosopher, best known for his 1818 work The World as Will and Representation)