Moreover, if we look at the techniques of totalitarian government, it is obvious that the argument of “the lesser evil” — far from being raised only from the outside by those who do not belong to the ruling elite — is one of the mechanisms built into the machinery of terror and criminality. Acceptance of lesser evils is consciously used in conditioning the government officials as well

Hannah Arendt (1906-1975) German-American philosopher, political theorist
Essay (1964-08), “Personal Responsibility Under Dictatorship,” The Listener Magazine
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Collected in Responsibility and Judgment, Part 1 "Responsibility" (2003).