...I am always amazed when I hear people saying that sport creates goodwill between the nations, and that if only the common people could meet one another at football or cricket, they would have no inclination to meet on the battlefield. Even if one didn't know from concrete examples (the 1936 Olympic Games, for example) that international sporting contests lead to orgies of hatred, one could deduce it from general principles.

...On the village green, where you pick up sides and no feeling of local patriotism is involved, it is possible to play simply for the fun and exercise: but as soon as the question of prestige arises,... the most savage combative instincts are aroused. Anyone who has played even a school football match knows this.... But the significant thing is not the behaviour of the players but the attitude of the spectators: and, behind the spectators, of the nations who work themselves into furies over these absurd contests, and seriously believe -- at any rate for short periods -- that running, jumping and kicking a ball are tests of national virtue.

-- George Orwell (1945)