When Machiavelli advises the Prince to carry out the Machiavellian scheme of action, he invests those actions with no sort of morality or beauty. For him morality remains what it is for everyone else, and does not cease to remain so because he observes (not without melancholy) that it is incompatible with politics. … For him evil, even if it aids politics, still remains evil. The modern realists are the moralists of realism. For them, the act which makes the State strong is invested with a moral character by the fact that it does so, and this whatever the act may be. The evil which serves politics ceases to be evil and becomes good.

pp. 107-108 - Treason of the Intellectuals (1927)