Public policy, foreign and domestic, should never be thought of as a duty to reduce the probability of even a highly feared contingency to zero, regardless of the costs of trying to do so. Public policy is necessarily a matter of weighing non-zero risks and costs of various contingencies and objectives, with the pursuit of some objectives being unavoidably in conflict with the pursuit of other objectives. This means that even the most carefully constructed policy will see some failures. 

Paul Pillar retired in 2005 from a twenty-eight-year career in the U.S. intelligence community, in which his last position was as a National Intelligence Officer for the Near East and South Asia. Earlier he served in a variety of analytical and managerial positions, including as chief of analytic units at the CIA covering portions of the Near East, the Persian Gulf, and South Asia. Professor Pillar also served in the National Intelligence Council as one of the original members of its Analytic Group. He is also a Contributing Editor for this publication.

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