For Janis Gregory, it's the whispers, the muted weeping and the soft shuffle of feet she remembers hearing in the Capitol rotunda as she waited 12 hours to see her president's coffin.
As a 16-year-old growing up in the Washington, D.C., area in 1963, Gregory said, the assassination of John F. Kennedy was a profound moment that awakened her mind to the world around her.
"For people who were young and idealistic when Kennedy was shot, that became their defining moment," Gregory, 56, said recently as she toured the assassination site outside The Sixth Floor Museum at Dealey Plaza (search). "It was horrific and it made a man who was invulnerable, vulnerable."
But for younger Americans who didn't live through the assassination, the significance of Nov. 22, 1963, and the events that followed centers more on the mystery of whodunit than the loss of a beloved president.
"We appreciate the conspiracy more than the loss because we weren't there," said Sarah Husbands, 27, who runs a bail bonds business in Houston. "We didn't experience the loss. We don't know what it was like."
While many older Americans can remember exactly where they were, what they were doing and how they felt when Kennedy was shot, many younger visitors to The Sixth Floor Museum (search) said their knowledge of the assassination was limited to movies, TV shows and history textbooks.
"They don't understand the nation's fascination with Jackie Kennedy. They don't have an appreciation for the real, tangible fear adults experienced during the Cold War years," said Gary Mack, curator of the museum. "And their knowledge of the Kennedy assassination, if they have any, mostly comes from the Oliver Stone film."
Mack said the museum was designed for those who remember the tragedy, not those learning about it. But he said changes are planned to appeal to a younger audience, including an exhibit on Oliver Stone's 1991 "JFK," which introduced a whole new generation to the assassination and to the conspiracy theories.
Stone's film centered on a theory by New Orleans District Attorney Jim Garrison (search) that a CIA-led mutiny killed the president and the plotters walked away unscathed. Garrison's theories went to court in 1967, but Clay Shaw, the alleged "evil genius" behind the assassination, was acquitted.
Marquette Wolf, a 33-year-old Dallas lawyer who works downtown, regularly observes tourists visiting the museum. He said one can tell a lot about a person's age or generation by where his or her camera is pointed.
"The grassy knoll seems to be the major focus of intrigue. You don't see many people taking pictures of the sixth floor," Wolf said. "It is the intrigue, that's why it's a draw."
Conspiracy theorists believe that there was more than one shooter, and that the bullet that killed Kennedy came from a sniper situated on the grassy knoll, not from Lee Harvey Oswald and the sixth floor of the Texas Book Depository.
Judy Graves, 50, of Cleburne was one of the few aiming her camera at the sixth floor. She remembers her fourth-grade teacher crying as she delivered the news of the assassination to her class, and her mother not cooking dinner. The family sat around a flickering black and white TV for days.
"I mean the world stopped," Graves said.
Her friend, Virginia Hubbard of Godly, remembers the fear.
"I was scared to death that night as we went to bed," said Hubbard, who was in the eighth grade when Kennedy was killed. "I thought Hitler and the communists were going to take over."
Older Americans say they've tried to translate their memories and emotions to their children and grandchildren.
"When there are events that change world history as you know it in your lifetime, it's almost like it's an honor to be alive and it's also an obligation to pass it down to younger people who were not alive," said Gregory, who now lives in Columbia, Md.
But something always gets lost in translation, older folks say. It's hard to relay the horror of the shooting to a generation of Americans who have become accustomed to violence on TV and in movies.
Many younger Americans who lived through the Oklahoma City bombing and the Sept. 11 terrorist attacks said they can imagine the national mourning that followed the assassination.
But many — familiar only with Kennedy's toothy grin and stories of marital infidelities — find it hard to understand the hope many Americans felt during Kennedy's presidency, the inspiration from his ideas on volunteerism and civil rights, the energy his youth and vigor generated, and the genuine love many Americans felt for Kennedy, his stylish wife and their two small children.
"People wept," said Randy Durr, a 45-year-old schools superintendent in Montana. "If President Bush was assassinated in the same way today, you kind of wonder if he would get the same reaction."
Randy Carter, a 27-year-old Air Force member from Denton, said the notion of Kennedy as a hero or a visionary is simply a product of his assassination.
"Had he finished out his term, I think he would be just another Democratic president," said Carter, who admits his interest in Kennedy revolves solely around the unsolved mystery of his death.
But John Nunley, 56, of Long Island, N.Y., said it's not just the young people who have lost sight of the tragedy.
"I think pain just has a short memory," said Nunley, a manager of an aviation service company. "How much homage do we pay to Pearl Harbor nowadays and when will 9-11 slip into our forgotten memory?"
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