Even the most powerful men in the world are human-they get sick, take dubious drugs, drink too much, contemplate suicide, fret about ailing parents, and bury people they love. Young Richard Nixon watched two brothers die of tuberculosis, even while doctors monitored a suspicious shadow on his own lungs. John Kennedy received last rites four times as an adult, and Lyndon Johnson suffered a "belly buster" of a heart attack. David Blumenthal and James...