Washington - The Lorraine Motel in Memphis, Tennessee, where he was shot 40 years ago, has been turned into the National Civil Rights Museum.
His birthday has become a national holiday, and every US school child and adult knows his name.
On Friday, the United States will mark the 40th anniversary of the assassination of Martin Luther King Jr, the civil rights leader who shook the country out of its apartheid past and led one of the country's most historic social movements ever.
King was struck down by a sniper at age 39 as he stepped onto a balcony at the Lorraine Hotel for a breath of air during a labour strike in Memphis.
His assassin, James Earl Ray, a white man obsessed with hatred for blacks who hoped he would be paid by segregationists for his deed, had stalked him from city to city across the Deep South until he had his chance. He was convicted and died in jail in 1998.
The April 4, 1968, assassination triggered country-wide race riots in which more than 40 people died and neighbourhoods were destroyed.
While much remains to be done - the high school drop out rate among black teenagers is still appalling - much has also changed. The prospect that America could elect its first black president, Barack Obama, in November has electrified the US political scene and bears witness to the radical progress in a society that once practised apartheid in many of its states.
King led efforts to end laws prohibiting blacks from using the same facilities as whites, enlisting thousands in nonviolent marches and sit-ins to halt the segregation laws that kept blacks and whites separated at schools, restaurants, public buildings and buses across the South.
The ordained Baptist minister's activism began in 1955, when Rosa Parks, a black woman, refused to give up her seat on a Montgomery, Alabama, bus to a white man, leading to her arrest and prompting a year-long-plus boycott of the buses.
The protest propelled King to the forefront of the civil rights movement that, through intervention by courts, Congress and state legislatures, integrated schools, secured voting rights and opened up services to African Americans.
Much of the progress was embedded in the Civil Rights Act signed into law by President Lyndon Johnson in 1964.
Funds are being raised for a King monument alongside those of US presidents on Washington's National Mall - where he gave his most famous speech, 'I have a dream,' in 1963 during the famed march on Washington.
The proponent of non-violence faced deep resentment from whites seeking to preserve the racist legacy that lingered after the abolition of slavery 100 years before, and also from civil rights leaders like Malcom X, who sought a more radical approach.
Today, African Americans make up about 13 per cent of the population, but many face disparities in income and education, and about 25 per cent live in poverty, US Census Bureau figures show.
Young black men have a tough time finding jobs, and make up a disproportionate percentage of the country's prison population.
Race still permeates US politics, surfacing in the presidential campaign, where Obama hopes to get the Democratic party nomination, and in the 2005 Hurricane Katrina, which laid bare the poverty of a black community unable to escape rising flood waters.
Jesse Jackson, one-time presidential candidate and a civil rights leader, calls repeatedly for the US to move on to the 'unfinished business of civil rights - which is civil equality,' he said. 'Our goal was never just freedom. Freedom was the necessary prerequisite to get to equality.'
Obama in Mid March had to address concerns about his minister, who made racially charged remarks suggesting Democratic party rival Hillary Clinton could not relate to African Americans because she had never been called by a racial epithet.
In a speech aimed at distancing himself from his minister, Obama pointed to the 'complexities of race in this country that we've never really worked through.' He noted the resentment on both sides of the racial divide, and called for blacks to stop nourishing their own sense of victim-hood and for whites to give up resentment at seeing job preferences for minorities under quota rules.
At the end of his life, King himself seemed resigned to the fact that he would not live to see the fruits of his efforts, but believed there would be success.
In a speech supporting striking sanitation workers the night before he died, King said it would not matter if he lived to see racial equality.
'I've seen the promised land,' King bellowed to the cheering crowd. 'I may not get there with you. But I want you to know tonight, that we, as a people, will get to the promised land.'
USA
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