Hitherto acceptable norms of human conduct do not apply. If the United States is to survive, long-standing American concepts of 'fair play' must be reconsidered. We must develop effective espionage and counterespionage services and must learn to subvert, sabotage and destroy our enemies by more clever, more sophisticated, and more effective methods than those used against us. It may become necessary that the American people be made acquainted with, understand and support this fundamentally repugnant philosophy.
-- Statement by World War II Gen. James Doolittle explaining in a secret 1954 report to President Eisenhower why CIA covert operations were needed and what they entailed; from Katherine S. Olmstead's book - Challenging the Secret Government, 1996