Americans will today commemorate the 50th anniversary of civil rights hero Martin Luther King Jr's historic "I have a dream speech".
America's first black President Barack Obama will mark the occasion in Washington DC with an address from the exact spot that King made an oration which went down in history on 28 August 1963.
In his speech from the steps of the Lincoln Memorial King laid out a powerful vision of democracy "deeply rooted in the American dream . . . 'that all are created equal.'"
King envisioned that all Americans, including racial minorities, would not only have unfettered access to vote, but, more important, have an urgent reason to go to the polls.
"We cannot be satisfied," King said, "as long as the Negro in Mississippi cannot vote and the Negro in New York believes he has nothing for which to vote."
The year after King's speech, President Lyndon B. Johnson was able to pressure Congress to pass the Civil Rights Act of 1964. He followed this with the Voting Rights Act of 1965. This bill, in particular, was born out of profound violence and deep-seated resistance, which King described as a "century of terror and evasion."
President Obama has described King's protest speech as a "seminal event" in American history.
He will deliver his own address at 3pm local time (7pm GMT), the exact time that King spoke 50 years ago.
In the audience will be former Presidents Bill Clinton and Jimmy Carter as well as members of the King family and veterans of the original protest march.
Last weekend saw thousands, including King's eldest sons, march on Washington to commemorate the civil rights milestone precipitated by King's speech - a move emblematic of the 250,000 protesters who stood listening on the same spot five decades earlier.
Watch footage of Martin Luther King Jr from 1963 above