JFK's legacy: How one President's untimely death shaped modern America

JFK and his wife Jackie arrive in Dallas one hour before he was shot and killed. Credit: JFK Library/The White House/Cecil Stoughton

Later today the city of Dallas will host a ceremony to mark the moment, 50 years ago, when a sniper fired three bullets at President Kennedy's motorcade.

Two hit their target and the world was changed forever.

Americans of that generation, now mostly retired, will always remember where they were when the news broke of the assassination.

A mournful America remembers JFK on 50th anniversary of his assassination

That day in Dallas occurred at the intersection of political tumult, a horrifying news event and the birth of television news.

So the killing of a youthful and optimistic President was captured on video and became etched into the soul of America.

The legacy of John F Kennedy was magnified exponentially by his tragic death. Historic civil rights legislation was passed as a posthumous tribute.

Americans pursued his dream of the Peace Corps, of reaching the moon, and they believed - unlike many of Kennedy's Generals - that the Cold War could be contained.

Conspiracy theorist Alex Jones led a rally in Dallas yesterday. He believes the truth about Kennedy's assassination was covered up. Credit: Reuters/Jim Bourg

There is another feature from 50 years ago that has endured: The conspiracy theory and a deep distrust of government.

Even today, 62% of Americans do not believe that a single sniper killed President Kennedy Most believe there was a cover-up.

Even his nephew, Robert Kennedy Jr, told me this week that he doubts the official version of the assassination.

Robert Kennedy Jr said his father was sceptical about the official version of JFK's death. Credit: ITV

Watch JFK's nephew on why his father thought the CIA was involved

Kerry Kennedy described her uncle's death as "a loss of innocence" Credit: Daybreak

Read the letter from Robert Kennedy to his daughter about JFK's assassination

Of course whether the CIA was to blame, or the Mafia, or the Russians, or the Cubans - that is still fiercely debated.

We may never know what really happened, and who was behind it, but as America lost its youngest ever President, this country was catapulted into a world of grief and scepticism.

Video: JFK's legacy can 'still be felt today'

The casket of former U.S. President John F. Kennedy is placed in the Capitol Rotunda in Washington, on November 24, 1963. Credit: REUTERS/The John F. Kennedy Presidential Library/Handout

John F Kennedy's legacy is profound and enduring.

Democrats still pay homage to his extraordinary charm and charisma. Strategists still admire his handling of The Cuban missile crisis.

Americans still rank him as one of the nation's most popular presidents.

We will never know if Kennedy would have saved America from the quagmire of Vietnam or what his second term would have looked like.

But we do know that JFK, despite facing virulent opposition in some quarters, had a remarkable hold over the imagination of Americans.

Those two bullets, while killing a President, has not changed that. Today's ceremonies will show the special relationship between Americans and their 35th President remains undimmed.

President Obama and former President Clinton lay a wreath at the JFK memorial at Arlington National Cemetery Credit: Reuters