By Nick Bryant
BBC News, Washington
To measure fully the historical achievement of Barack Obama's victory it is worth recalling what America looked like in 1961, the year of his birth.
Back then, much of the American South remained segregated, the races separated from the cradle to the grave.
Black people - or Negroes as they were known then - were born in segregated hospitals, educated in segregated school systems and buried in segregated graveyards.
Handed down in 1954, the Supreme Court's Brown decision, which called for the integration of southern schools, had been met in many southern communities with a campaign of "massive resistance".
For segregationist die-hards it became the twisted metaphor of the age, as they fought to uphold a system of racial apartheid that was known by the deceptively friendly aphorism, Jim Crow.
Washington DC was regarded still as a hardship posting for African diplomats, despite the efforts of Presidents Truman and Eisenhower to desegregate the nation's capital.
Restrictive covenants prevented them from living in the most fashionable parts of town, and they were denied service in the high-end barber shops.
When they made the journey to the United Nations in New York, they travelled a road, Route 40, which was lined with segregated motels, diners and restaurants.
Back at the start of the 1960s, America's first black presidential aide, a former public relations man called E Frederic Morrow, published a memoir of his years working under Dwight D Eisenhower.
It was titled Black Man in the White House. It revealed how he was never allowed to be left alone in the same room as a white woman, such was the fear that he might sexually molest her.
On becoming president in 1961, Jack Kennedy made a series of senior black appointments. Still, the young president's most valued African-American aide was a man called George Thomas, whose job each morning was to lay out his clothes.
Leaving others to attach racial meaning to his candidacy, Barack Obama has not spoken much about the struggle for black equality, nor the tumultuous decade into which he was born.
Go through his speeches, and you will find little mention of the civil rights era.
For to become a history-defying candidate he has been something of a history-denying figure. The strategy throughout has been to de-emphasise his race.
A quirk of scheduling and a quantum leap of history meant that Mr Obama delivered his acceptance speech in Denver on the 45th anniversary of Martin Luther King's I Have a Dream speech.
But even then, Mr Obama did not mention Dr King by name, referring to him instead as the "young preacher from Georgia".
Black and white
Back in June, on the night when he finally saw off the challenge from Hillary Clinton, his celebration speech made no reference to his historic racial first, and noticeably he dedicated his victory to his white grandmother.
Throughout the campaign, Mr Obama has emphasised his whiteness as much as his blackness.
Martin Luther King spoke of his dream for America 45 years ago
The president-elect understood one of the great paradoxes of the civil rights era.
While it helped pave the way for his ultimate success, it also made it more difficult for northern candidates, like him, to win the presidency.
When President Lyndon Johnson signed the landmark 1964 Civil Rights Act into law, he told an aide: "We have lost the south for a generation". But he had miscalculated.
The once solid Democratic South - the Democrats used to be an unhappy alliance between Northern moderates and progressives, and southern segregationists - started to go reliably Republican in presidential elections.
Prior to 1964, the Democrats won six out of eight presidential elections. After 1964, they lost seven out of 10.
Achieving the impossible
The civil rights era was responsible for the great historical anomaly of US post-war politics: the process through which the party of Abraham Lincoln, the Great Emancipator, established a stronghold in the states of the Old Confederacy.
It is no coincidence that every Democratic president since the passage of the 1964 Civil Rights Act has hailed from the south: Jimmy Carter, Bill Clinton and, the die-hards would contest, Al Gore.
The new law not only demolished segregation, but re-drew the US political map.
So it is worth remembering that Barack Obama will not only be the first African-American president, but the first Northern Democrat to serve in the White House since Kennedy.
To achieve this racial first represents the most extraordinary of achievements.
Since the end of Reconstruction - the period in the aftermath of the US civil war - there have been just three black US senators.
Only two states, Massachusetts and Virginia, have elected a black governor.
With the election of a black president, what many considered the politically impossible has now become real.
On 28 August 1963, Martin Luther King spoke of his dream for America, with the brooding statue of Abraham Lincoln offering the most glorious of pulpits.
On 20 January 2009, Barack Obama will appear on the west steps of the US Capitol, at the other end of the Washington Mall, and seal his historic triumph with just 35 words: the presidential oath of office.
Nick Bryant is the author of The Bystander: John F. Kennedy and the Struggle for Black Equality