A career of nearly three decades with the CIA and the National Intelligence Council showed Paul R. Pillar that intelligence reforms, especially measures enacted since 9/11, can be deeply misguided. They often miss the sources that underwrite failed policy and misperceive our ability to read outside influences. They also misconceive the intelligence-policy relationship and promote changes that weaken intelligence-gathering operations.

In this book, Pillar confronts the intelligence myths Americans have come to rely on to explain national tragedies, including the belief that intelligence...