Standing on the steps of the Lincoln Memorial to mark the 50th anniversary of King's "I Have a Dream" speech, Clinton said Americans should do less griping and more working to make things better.
"It is time to stop complaining," he said, and "put our shoulders against the stubborn gates" that are holding the American people back.
Just paces away sat President
Clinton suggested that Americans can stand up even when the law tilts against them, as it did for black Americans trying to exercise their right to vote in the Jim Crow South.
"They showed up, stood in lines and voted anyway," Clinton said.
But he voiced support for Obama's efforts to reform the U.S. healthcare system, as well as his attempts to pass federal gun control legislation.
"A great democracy does not make it harder to vote than to buy an assault weapon," he said.
Clinton spoke as a son of the white South, recalling how he listened to the King speech in 1963 alone in his Arkansas home.
In a speech almost as heavy on politics, former
"We all know how Dr. King would have reacted," Carter said, to the Supreme Court's decision to strike down a crucial provision of the Voting Rights Act, as well as to high black unemployment and to "our country being awash in guns."
He would have kept working for the cause of freedom, Carter said.
"In truth," he said, "he helped to free all people."