Americans have always had their differences and disagreements, but rarely have they been more polarized than today. President Barack Obama is at his lowest approval rating ever, 39 percent. Even so, he ranks higher than the Republican Party, which is viewed favorably by only 28 percent of Americans.
Both have made mistakes in recent months and years that have damaged their standing. But both are victims of a populace that is generally suspicious, disenchanted and even hostile toward their leaders. When one side loses favor with the public, the other doesn't seem to gain.
We have come to accept this acrid, pessimistic climate as a fact of life. But it wasn't always. That's one of the reasons that so many Americans of a certain age look back with yearning to the presidency of John F. Kennedy.
He endures in memory not only as a president but as a symbol of a time of comparative unity, hope and confidence. His assassination was a tragedy, but it was also a harbinger. What lay ahead, as Americans now know, was an unraveling of our civic fabric, which has not been and may never be restored.
In 1958, when asked if they trusted the federal government to do the right thing most of them time, 73 percent of Americans said they did. Today the figure is just 19 percent.
When Kennedy called on his fellow citizens to ask what they could do for their country, they were inclined to take him seriously. Political leaders no longer make such requests because they know what sort of reception they would get.
What was so different about that era? One reason for the general assumption that the government was capable of overcoming big challenges was recent experience of it doing just that.
Under Franklin D. Roosevelt, Washington had taken a host of drastic measures to reverse the Great Depression and help those hurt by it. Some worked and some didn't, but eventually the economy rebounded, and ordinary people had new protections against hardship.
In World War II, leaders mobilized the nation to overcome a mortal danger. A government that could defeat Germany and Japan was assumed to be competent and useful.
Americans in 1963 also had a compelling incentive for unity: the menace posed by a nuclear-armed ideological enemy. The Cold War had gone on for most of two decades, and the Soviet menace seemed to be growing more formidable all the time. In 1962, the superpowers had come to the brink of nuclear war over Cuba. Kennedy inspired hope -- but shadowing that hope was the ceaseless fear of communist enslavement or World War III.
There was another reason the public was inclined to place confidence in the federal government: the federal government did far less than it does today. The Washington bureaucracy had no departments devoted to energy, education, housing and urban development, transportation, veterans affairs or homeland security.
Defense spending accounted for 47 percent of the federal budget. Payments for individuals took 27 percent. Today, the figures are 18 percent and 66 percent. JFK's government had narrower responsibilities, principally national defense and Social Security -- two functions that appeared to be well within its ability to handle.
What happened in the years after his death was a series of calamities that spread turmoil and alienation. Crime soared. Riots devastated cities. More assassinations took place.
In Vietnam, the nation plunged into a long, bloody and inconclusive war that ignited mass protests and campus upheaval.
The Watergate scandal exposed a paranoid president bent on subverting the Constitution. An energy crisis erupted. Inflation rose higher and higher.
The angry upheaval eventually subsided, and some of the other problems were solved or curtailed. But these events left deep scars and permanent anxieties that have been transmitted even to younger people who grew up later.
In the six years after the assassination, wrote political scientists Seymour Martin Lipset and William Schneider in 1983, "there was a virtual explosion of anti-government feeling" -- from both the right and the left. By now, the sense of common purpose and optimism that Kennedy relied on seems as distant as that day in Dallas.
After the assassination, journalist Mary McGrory told Daniel Patrick Moynihan, then assistant secretary of labor, "We'll never laugh again." He replied: "Mary, we'll laugh again. It's just that we'll never be young again." America, too, irretrievably lost some of the bright dreams of youth on Nov. 22, 1963.
As we approach the sad 50th anniversary of this shocking event, Americans may ask themselves why we have no leaders with Kennedy's capacity to inspire and motivate. The answer lies not so much in our leaders as in ourselves.