DALLAS -- Thousands of mourners, conspiracy theorists and the just plain curious gathered Saturday along the downtown street where President John F. Kennedy was assassinated 40 years earlier, with many of them recalling where they had been at the very moment they heard the news.
Some looked up to the sixth floor of the former Texas School Book Depository, the building from which officials say Lee Harvey Oswald fired the deadly shots at 12:30 p.m. on Nov. 22, 1963. Others gravitated toward an "X" painted on the pavement to mark the spot where Kennedy's convertible was passing when he was hit.
A makeshift memorial with dozens of bouquets, signs and flags of the U.S. and other countries was assembled nearby -- one of several memorials around the country for the fallen president.
"John F. Kennedy has been gone nearly as long as he lived, yet the memory of him still brings pride to our nation and a feeling of loss that defies the passing of years," President Bush said in a written statement.
Near Washington, Kennedy family members gathered at Arlington National Cemetery early in the day to pray beside the eternal flame that marks the president's grave.
Kennedy's daughter, Caroline Kennedy, her husband and children, and Kennedy's brother, Sen. Edward M. Kennedy, D-Mass., were joined by Cardinal Theodore McCarrick, archbishop of Washington.
The cemetery opened to the public after the family left. Many visitors left flowers, photographs of President Kennedy, poems and American flags.
Washington-area resident Steve Prindle echoed the sentiments of many others on Saturday: "One always wonders what might have been."
Standing at Dealey Plaza in Dallas, Jim Johns remembered being in his seventh-grade class when the announcement of Kennedy's assassination came over the school intercom.
"It was devastating," said Johns, 52, of Houston. "My teacher started crying, all the girls started crying, all the boys started cursing the Russians -- that's who we thought it was. It was terrible. We all wanted to go to war."
Dallas police blocked off Elm Street -- the site where Kennedy was shot -- for the commemoration, but the city did not conduct a formal service.
As 12:30 p.m. neared, a bellowing voice narrated the seconds leading up to the fatal shots from a sound stage on the grassy knoll, where some people believe other shots were fired. Drummers in blue and plaid solemnly marched down Elm Street.
In the moment of silence that followed, a few were heard crying.
The sound stage was set up by JFK Lancer, a group that promotes research into conspiracy theories of the assassination. Former Minnesota Gov. Jesse Ventura spoke on the conspiracy theorists' behalf.
In Boston, the John F. Kennedy Library and Museum screened a montage of Kennedy video clips, including his first televised press conference and a 1960 appearance on "The Jack Paar Show."
Condolence letters to the family were on display, including one from the Rev. Martin Luther King Jr. and his family, and another from schoolchildren in Kuwait.
Museum visitor Carol Grey, 57, of Hanover, Mass., said she was in her high school "Problems of Democracy" class when she heard the news.
"You didn't leave your house for days," she said. "Similar to 9-11. The shock that someone could do something like that."
Jean Healey, of Braintree, Mass., came to the museum with her son and granddaughter. Now semiretired, Healey was a young mother of four in 1963, and remembered on Saturday how Kennedy inspired hope and optimism.
"There was such hope in the hearts and minds of everyone. The exuberance, the enthusiasm, the wit, the intelligence, and the bright hope of a new generation just permeated all of us," she said. "He was a hopeful sign of a different turn in our society."
Some Dallas residents recalled the shame of having an unspeakable tragedy happen in their back yard.
Bruce Goldston, 53, recalls his social studies teacher saying, "They ought to wipe Dallas off the map."
"We were so sad that it happened in our town," said Bette Pritchett, 63, who lived in Dallas at the time. "It was just a big black mark and we couldn't undo it."