On the other hand, the cheapest form of pride is national pride; for the man affected therewith betrays a want of individual qualities of which he might be proud, since he would not otherwise resort to that which he shares with so many millions. The man who possesses outstanding personal qualities will rather see most clearly the faults of his own nation, for he has them constantly before his eyes. But every miserable fool, who has nothing in the world whereof he could be proud, resorts finally to being proud of the very nation to which he belongs. In this he finds compensation and is now ready and thankful to defend, “tooth and nail,” all the faults and follies peculiar to it.

[Die wohlfeilste Art des Stolzes hingegen ist der Nationalstolz. Denn er verrät in dem damit Behafteten den Mangel an individuellen Eigenschaften, auf die er stolz sein könnte, indem er sonst nicht zu dem greifen würde, was er mit so vielen Millionen teilt. Wer bedeutende persönliche Vorzüge besitzt, wird vielmehr die Fehler seiner eigenen Nation, da er sie beständig vor Augen hat, am deutlichsten erkennen. Aber jeder erbärmliche Tropf, der nichts in der Welt hat, darauf er stolz sein könnte, ergreift das letzte Mittel, auf die Nation, der er gerade angehört, stolz zu sein. Hieran erholt er sich und ist nun dankbarlich bereit, alle Fehler und Torheiten, die ihr eigen sind, mit Händen und Füßen zu verteidigen.]

Arthur Schopenhauer (1788-1860) German philosopher

Parerga and Paralipomena, Vol. 1, “Aphorisms on the Wisdom of Life [Aphorismen zur Lebensweisheit],” ch. 4 “From What One Imagines [Von dem, was einer vorstellt]” (1851) [tr. Payne (1974)]
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(Source (German)). Alternate translation:

The cheapest sort of pride is national pride; for if a man is proud of his own nation, it argues that he has no qualities of his own of which he can be proud; otherwise he would not have recourse to those which he shares with so many millions of his fellowmen. The man who is endowed with important personal qualities will be only too ready to see clearly in what respects his own nation falls short, since their failings will be constantly before his eyes. But every miserable 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 glad to defend all its faults and follies tooth and nail, thus reimbursing himself for his own inferiority.
[tr. Saunders (1890)]

The cheapest form of pride however is national pride. For it betrays in the one thus afflicted the lack of individual qualities of which he could be proud, while he would not otherwise reach for what he shares with so many millions. He who possesses significant personal merits will rather recognise the defects of his own nation, as he has them constantly before his eyes, most clearly. But that poor beggar who has nothing in the world of which he can be proud, latches onto the last means of being proud, the nation to which he belongs to. Thus he recovers and is now in gratitude ready to defend with hands and feet all errors and follies which are its own.
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