Celebrities, a half-dozen lawmakers and protesters from distant states rallied in the capital under a sunny sky, seizing an opportunity to press their cause with a Congress restive on the war and a country that has turned against the conflict.
Marching with them was Jane Fonda, in what she said was her first anti-war demonstration in 34 years.
"Silence is no longer an option," Fonda said to cheers from the stage on the National Mall. The actress once derided as "Hanoi Jane" by conservatives for her stance on Vietnam said she had held back from activism so as not to be a distraction for the Iraq anti-war movement, but needed to speak out now.
But for all the tie-dye and familiar chants, the anti-war movement has moved on — and changed direction, reports CBS News correspondent Joie Chen.
Today's protest didn't go near the White House. Instead, tens of thousands walked Constitution Avenue to the Capitol, bearing a message for the new, democratically controlled, Congress.
"I think the Democrats are well aware that a lot of Democrats were elected this year over Republicans because of this issue," said protester Connie Gordon.
The rally on the Mall unfolded peacefully, although about 300 protesters tried to rush the Capitol, running up the grassy lawn to the front of the building. Police on motorcycles tried to stop them, scuffling with some and barricading entrances.
Protesters chanted "Our Congress" as their numbers grew and police faced off against them. Demonstrators later joined the masses marching from the Mall, halfway around Capitol Hill and back.
United for Peace and Justice, a coalition group sponsoring the protest, had hoped 100,000 would come. Police, who no longer give official estimates, said privately the crowd was smaller than that.
At the rally, 12-year-old Moriah Arnold stood on her toes to reach the microphone and tell the crowd: "Now we know our leaders either lied to us or hid the truth. Because of our actions, the rest of the world sees us as a bully and a liar."
The sixth-grader from Harvard, Mass., organized a petition drive at her school against the war that has killed more than 3,000 U.S. service-members.
More Hollywood celebrities showed up at the demonstration than buttoned-down Washington typically sees in a month.
Actor Sean Penn said lawmakers will pay a price in the 2008 elections if they do not take firmer action than to pass a nonbinding resolution against the war, the course Congress is now taking.
"If they don't stand up and make a resolution as binding as the death toll, we're not going to be behind those politicians," he said. Actors Susan Sarandon and Tim Robbins also spoke.