Bernice King and her brother Martin Luther King III said their father's dream is not yet realized. Martin Luther King III said the nation has "lost its soul" when it tolerates vast economic disparities, teen bullying, and having more people of color in prison than in college.
He said the memorial should serve as a catalyst to renew his father's fight for social and economic justice.
"The problem is the American dream of 50 years ago ... has turned into a nightmare for millions of people" who have lost their jobs and homes, King said.
The nation's first black president, who was just 6 years old when King was assassinated in 1968, saluted King as a man who pushed the nation toward what it ought to be and changed hearts and minds at the same time.
"He had faith in us," Obama said. "And that is why he belongs on this Mall: Because he saw what we might become."
Giovanni read her poem "In the Spirit of Martin," and Franklin sang.
Early in the ceremony, during a rendition of "Lift Every Voice and Sing," the crowd cheered when images on screen showed Obama on the night he won the 2008 presidential election.
Obama, who credits King with paving his way to the White House, left a copy of his inaugural speech in a time capsule at the monument site. He said King was a man who "stirred our conscience" and made the Union "more perfect."
But the Rev. Al Sharpton said the dedication was not about Obama but the ongoing fight for justice. He called for people from around the world to walk through the stone of hope and emerge to see "the face that brought us from the back of the bus to the White House."
Brett Zongker can be reached at http://www.twitter.com/DCArtBeat
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