(WASHINGTON) -- President Obama on Wednesday offered a tribute to the Rev. Martin Luther King Jr., while also imploring all Americans to remember that the work of the iconic civil rights leader remains unfinished. "The arc of the moral universe may bend toward justice, but it doesn't bend on its own," Obama said on the steps of the Lincoln Memorial on a rainy afternoon in Washington.
"We'll suffer the occasional setback, but we will win these fights." Obama, who spoke to an estimated crowd of 20,000 -- far fewer than the 200,000-plus who attended King's "I Have a Dream" speech 50 years ago -- recalled that day in 1963.
"On a hot summer day, they assembled here in our nation's capitol, under the shadow of the great emancipator to offer testimony of injustice, to petition their government for redress, to awaken America's long slumbering conscience," he said.
"How he gave mighty voice to the quiet hopes of millions, how he offered a salvation path to oppressed and oppressors alike. We would do well to recall that that day itself also belonged to those ordinary people whose names never appeared in history books."
Acknowledging his own place in history, Obama praised King and the civil rights activists of his era: "They kept marching, America changed."
He added, "and yes, eventually, the White House changed."
Fifty years to the day after King Jr. delivered his speech, Obama stepped into the shadows of his personal hero, standing in the same spot to deliver remarks commemorating the 1963 March on Washington, a powerful example of the progress King envisioned.
For the nation's first African-American president, the much-anticipated speech carried with it immense symbolism and high stakes.
Obama often cites King as one of the people he most admires, even though he was just 2 years old when the civil rights icon delivered his famous speech.
The president keeps a bust of King in the Oval Office and has on display a framed copy of the program from the 1963 March on Washington for Jobs and Freedom.
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