Robert Dallek’s latest book, “The Lost Peace: Leadership in a Time of Horror and Hope, 1945-1953,” has just been published in paperback.

Nov. 30 (Bloomberg) -- The historian Richard Hofstadter said that the U.S. is the only country in history that believes it was born perfect and strives for improvement. The idea that we are a nation without flaws or that we can permanently eliminate our very human failings is, of course, delusional....

The attraction to easy answers is echoed in a 2010 Gallup poll that asked Americans to assess the last nine presidents from John F. Kennedy to George W. Bush. Kennedy topped the list with an 85 percent approval rating. Only Ronald Reagan was in hailing distance of him, with 74 percent. Deciphering these results presents a challenge: Kennedy’s thousand days comprised one of the briefest presidencies in U.S. history. His slight record, devoid of major domestic legislative achievements, seems smothered by the country’s overwhelming regard.

High Esteem

Nor do Reagan’s White House accomplishments square with so robust a public endorsement. Yes, the Cold War sputtered toward its conclusion on his watch, but historians see Harry S. Truman’s containment policy as the principal cause of this national success -- not Reagan’s policies. Given current anxieties over economic uncertainties, including unprecedented sums of federal, state and local debt, Reagan’s eight-year presidency, which nearly tripled the nation’s debt, seems at odds with the public’s high esteem....

What gives Kennedy and Reagan such a strong hold on American imaginations is not what they did but what they said and still stand for. Both presidents are remembered as optimists promising better futures. Kennedy had the New Frontier; for Reagan, it was Morning in America. Both remain inspirational voices that in a time of doubt give people hope. And when you put either man alongside Richard Nixon, Gerald Ford, Jimmy Carter and George W. Bush, they seem especially appealing....