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
(Source)
Collected in Responsibility and Judgment, Part 1 "Responsibility" (2003).

