King "truly believed in the dignity of all human beings. It didn't matter if you were black, white, Latino, Native American," Lewis said.
Along with many other speakers at Sunday's ceremony, Lewis noted that at the time of King's assassination, he was working to build a multiracial coalition that would bring a "poor people's campaign" to the National Mall.
"There was a parallel (in Obama's speech) with what he's going through now, too," Lewis said. "When President Obama was running for office there was a low moment in his campaign, and he said, 'I have to go back to my authentic self.' I think what we saw here was authentic Obama. It was very powerful."
Powerful without dwelling directly on black or white, said Colin Powell, the Republican and first black secretary of state under President George W. Bush.
"This wasn't a speech about race," Powell said. "It was a speech about the future of America. He touched all the bases: where we have been, where we are going, where we are now, and where we have to be."
Not everyone was impressed. David Kairys, a Temple University law professor and civil rights attorney who attended King's 1963 March on Washington, wished Obama had provided a clear reckoning of remaining racial problems.
"This specific occasion is about the struggle against racial oppression," Kairys said, then mentioned that black unemployment is twice the white rate and blacks still suffer disproportionately from many social ills.
"We eliminated the worst forms of explicit racism and it became taboo to be racist, but the results of segregation and Jim Crow were basically left in place and just continued over the last 40 or 50 years," he said. "That's at least worth some kind of direct comment."
Yet he understood, in some way, why Obama made that choice: "To be fair, he's running for reelection. Also, he never told us he was going to be a champion against racial oppression. This (speech) is probably who he really is."
Most others were more complimentary. Even the conservative talk show host Mike Gallagher, who is determined to defeat the president in 2012, said that the way Obama honored King's legacy was "brilliant."
"It was a beautiful, powerful message about what can be achieved in this country," Gallagher said. "I really appreciate the fact that he acknowledged as a black man how much progress we've made. . And it kills me to say this, because I think Obama is wrecking the country."
Paul and Carol Cooper, a white retired couple from Kingston, NY, heard King's "Dream" speech in person in 1963. Before Sunday's speech, they had hoped Obama would discuss the work still undone to fulfill King's dream.
On Sunday, Paul Cooper called Obama's remarks a "classic."
"Obama showed us repeatedly," he said, "that King belongs not merely to black people, but to the whole country."
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