[Philip Bobbitt, a law professor at Columbia, is the author, most recently, of “Terror and Consent: The Wars for the 21st Century.”]

For Christmas in 1963 we gathered at the ranch that had belonged to my great-grandfather, a few miles outside the town — Johnson City — named for our family.

Lyndon Johnson, my uncle, presided over the noisy feast, and the unwrapping and the prayers. By the fire, that afternoon, he quizzed me on the cabinet he had inherited. I was 15, a high school senior. Could I name all the cabinet members? I could. Did I know which ones were from Wall Street, which ones had served in Congress, which ones had been governors? I did. It went on and on — not so unlike the quizzes he must have given his students 30 years earlier when he coached a high school debate team as a young teacher in Houston.

But now, he said, he had a question that was sure to stump me. Who was the most compassionate member of the cabinet? I guessed, rather unconfidently. Wrong. I guessed again, wrongly. He laughed and said: “You’ll never get it. It’s Bob McNamara. By far.” And it was a surprise, because we all thought of Bob McNamara as the no-nonsense numbers man from corporate America. The steel-rimmed glasses and the steel-trap mind were perfectly suited to an industrial mentality.
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