At the height of Ronald Reagan's popularity in July 1986, Time Magazine wrote glowingly of how he had "found America's sweet spot." Reagan seemed a "magician who carries a bright, ideal America like a holograph in his mind and projects its image in the air." Not since journalist Theodore White rhapsodized about "Camelot" in the wake of John F. Kennedy's assassination had a president been spoken of so reverently. And indeed, Reagan seemed to know just...