John F. Kennedy was a good president but not a great one, most scholars concur. A poll of historians in 1982 ranked him 13th out of the 36 presidents included in the survey. Thirteen such polls from 1982 to 2011 put him, on average, 12th. Richard Neustadt, the prominent presidential scholar, revered Kennedy during his lifetime and was revered by Kennedy in turn. Yet in the 1970s, he remarked: “He will be just a flicker, forever clouded by the record of his successors. I don’t think history will have much space for John Kennedy.”

But 50 years after his death, Kennedy is far from “just a flicker.” He remains a powerful symbol of a lost moment, of a soaring idealism and hopefulness that subsequent generations still try to recover. His allure—the romantic, almost mystic, associations his name evokes—not only survives but flourishes.