KING'S STRATEGY of mass mobilisation against segregation produced a violent reaction from the white supremacists.
King aimed to get the US government to end the international embarrassment of the apartheid system in the south.
The US was posing as the defender of democracy in its Cold War duel with Russia. US president John F Kennedy condemned Communist 'tyranny' in a famous speech in Berlin in 1963.
But the world had just seen pictures of police dogs and water cannon turned on black teenage protesters in Birmingham, Alabama, the citadel of US segregation.
The US government was forced to intervene to end legal segregation, fearing growing militancy at home and loss of influence abroad.
Civil rights were finally granted 100 years after the civil war.
But again the levers of economic power remained in the same hands.
The US state crushed movements which went beyond calls for legal reform and which fought for economic and social transformation as well.
Ruling class figures moved to co-opt a layer of middle class blacks.
Forty years on, legal segregation is no more.
But racist discrimination against blacks, Latinos and other minorities marks every area of life in the US.
There are more black men in prison or on probation than there are in college.
Almost three decades of attacks on the living standards of workers, black and white, has gone hand in hand with divide and rule.
Segregation in housing and education has actually risen over the last 15 years in many areas of the US, despite the civil rights laws.
In the year before he was assassinated Martin Luther King began to recognise just how closely racism and capitalism were linked.
He also made a stand against the Vietnam War.
The US establishment spied on and murdered black leaders, and the FBI under J Edgar Hoover was heavily implicated in King's assassination.
In 1967 he gave a speech as compelling, but more profound, than his address to the march on Washington four years previously. 'You begin to ask the question,' he said.
''Who owns the oil?' You begin to ask the question, 'Why is it that people have to pay water bills in a world that is two thirds water?'
'When I say question the whole society, it means ultimately coming to see that the problem of racism, the problem of economic exploitation and the problem of war are tied together. 'A nation that will keep people in slavery for 244 years will 'thingify' them, make them things.
'Therefore they will exploit them, and poor people generally, economically.
'And a nation that will exploit economically will have to have foreign investments and will have to use its military might to protect them. All of these problems are tied together.'