History repeats

To fit in with the change of events, words, too, had to change their usual
meanings. What used to be described as thoughtless aggression was now
considered the courage of a loyal ally; to think of the future and wait was
merely another way of saying one was a coward; any idea of moderation was
just an attempt to disguise one's unmanly character; the ability to
understand a question from all sides meant that one was totally unfitted for
action. Fanatical enthusiasm was the mark of a real man, and to plot against
an enemy behind his back was perfectly legitimate self-defense. Anyone who
held violent opinions could always be trusted, and anyone who objected to
them became a suspect. To plot sucessfully was a sign of intelligence, but
it was still cleverer to see that a plot was hatching. If one attempted to
provide against having to do either, one was disrupting the unity of the
party and acting out of fear of the opposition. In short, it was equally
praiseworthy to get one's blow in first against someone who was going to do
wrong, and to denounce someone who had no intention of doing any wrong at
all. Family relations were a weaker tie than party membership...

--Thucydides, History of the Peloponnesian War, 382