The United States paused to mark the 50th anniversary of the assassination of President John F. Kennedy on Friday with memorial ceremonies and moments of silence.
In Dallas, Texas -- the southwestern city where President Kennedy was assassinated as he rode in an open-air motorcade -- church bells chimed as several thousand people observed the solemnity of the exact moment he was shot on Dealey Plaza.
Dallas dedicated a new marker with words from a speech President Kennedy planned to give that day a half century ago, describing Americans as "watchmen on the walls of world freedom," and that the U.S. must strive to be worthy of its status as a global power to achieve peace.
The city was holding its first official commemoration of the event that some historians say marked a loss of innocence for the United States. Many older Americans have memories etched in their minds of November 22, 1963, of where they were when they heard the news.
Pulitzer Prize-winning historian David McCullough read from some of Mr. Kennedy's speeches, including one where he laid out the role of the United States in world affairs.
"The goal of a peaceful world is our guide for the present and our vision for the future. The quest is the greatest adventure of our century. We sometimes chafe at the burden of our obligation, the complexity of our decisions, the agony of our choices. But there is no comfort or security in evasion, no solution in abdication, no relief in irresponsibility."
President Barack Obama ordered flags across the United States to fly at half staff to honor the late president, who was gunned down late in the third year of his single term in office. Memorial events were held in several cities, including Washington and Boston, in (the northeastern state of) Massachusetts, where then-Senator Kennedy lived before winning the White House in the 1960 election.
Memorial events were also held in European capitals, including a wreath-laying ceremony in the Berlin neighborhood where President Kennedy, in a Cold War-era speech, told an adoring crowd of Germans, "Ich bin ein Berliner."
The CBS television network, on its website, live-streamed its original news bulletins from the shooting that shocked Americans and people across the world.
Mr. Obama has called his revered predecessor an "extraordinary public servant" who had broad vision and sober idealism. Mr. Obama laid a wreath at President Kennedy's grave at Arlington National Cemetery on Wednesday.
A survey of Americans (by CNN and ORC International) shows that President Kennedy is the most popular president of the last half century, with 90 percent approving of his handling of the presidency. No other U.S. president comes close to that rating.
Mr. Kennedy's presidency was about 1,000 days old and he was just 46 when he was shot dead while riding in an open-top limousine. The fatal shot destroyed most of the president's brain, shocking witnesses by its brutality.
The crime stunned the world and left even the president's adversaries, such as Soviet leader Nikita Khrushchev, grieving and speechless.
Most Americans spent the weekend in tears, watching the president's young widow, Jacqueline, and their two small children mourn publicly.
The president's assassin, Lee Harvey Oswald, was shot dead in police custody on live television two days after the death of the president. His motive will likely never be known. Oswald was a former U.S. Marine who defected to the Soviet Union in 1959, then returned to the U.S. in 1962.