Nationalism of one kind or another was the cause of most of the genocide of the twentieth century. Flags are bits of colored cloth that governments use first to shrink-wrap people's minds and then as ceremonial shrouds to bury the dead.
Friendship, love, and piety ought to be handled with a sort of mysterious secrecy; they ought to be spoken of only in the rare moments of perfect confidence, to be mutually understood in silence. Many things are too delicate to be thought; many more, to be spoken.