Painters create a mural on the boarded windows of the Park nightclub in the District on Saturday. (Toni L. Sandys/The Washington Post)

By noon, people were descending on the streets around the White House from all directions, a billowing crowd that included demonstrators hoisting “Black lives matter” signs and American flags.

Joe Marinucci, 65, standing alone, decided early Saturday over coffee to go to his first protest in over 40 years. He did not tell his sleeping wife, who would have insisted he stay home for fear of the coronavirus. Instead, he texted he was at the White House and then shut off his phone.

“I just can’t sit on the sidelines anymore,” said the retired geographer from Springfield, Va., his voice cracking with emotion as he stood in the street bordering Lafayette Square. “I can’t take it. It’s just so sad how America has come to this. Enough is enough.”

On a day that followed a week of protests over the death of George Floyd, the mass demonstration in sunny downtown Washington was the biggest yet — infused with a sense of celebration over a growing agreement that the country must meaningfully confront police brutality and racism.

But looming over the assembly was a question: Would this moment lead to a new way?

“It’s time for real change, not a photo op,” said Aisha Jackson, 62, a retired executive assistant who lives in the District, as she stood on 16th Street. All around her, people took pictures of the letters spelling out “Black lives matter” that had been painted across two blocks leading to the White House.

“Black power! All day, every day!” Jackson shouted as she wandered through the crowd. She said she wasn’t sure that the white people who have attended the protests would still be interested when the intensity surrounding Floyd’s death abates.

“White people walked with Dr. King, and when the dust settled they went back to their white privilege,” Jackson said. “The real test is about the redistribution of wealth. People talk a good game but when it comes to money and resources it’s still white supremacy. Is that going to change?”

This was no time to ease up, she said.

“They’re killing our children!” she shouted at strangers who paused to listen and record her with their iPhones. “We ain’t taking it anymore! It’s a damn shame I even have to be out here anymore!”

Steve Morrison, 64, a white Foreign Service officer pointed to his presence as evidence of a significant shift.

“I am the deep state — advocating for our country and our way of life is my job,” he said, describing himself as a “militant centrist” as he held a sign that read, “Thank You Protesters, BLM!”

“The level of anxiety in my home over these issues is palpable,” he said. “I just don’t think Americans can stand by anymore.”

For generations, protests have been a ritual ingrained in the fabric of Washington, the backdrop for iconic gatherings such as King’s “I Have a Dream” speech, antiwar demonstrations during the 1960s, the Million Man March and the Women’s March that followed Trump’s inauguration.

But it can take years for laws and policies to change.

The protesters had just emerged from under clouds of tear gas and contentious showdowns with police. On Saturday, the storm clouds had cleared and a festive spirit filled the air.

Rap and funk music blared as people danced, ate ice cream and strolled along 16th Street toward the White House, some pushing strollers, others walking dogs.

Volunteers handed out water and snacks and vendors sold T-shirts, one of which was emblazoned on one side with the words, “I Can’t Breathe.” On the other side was the image of Minneapolis police officer Derek Chauvin kneeling on Floyd.

“I wanted to make it as graphic as possible,” the vendor, Wilbert Drew, 67, said.

As she posed for photos a few feet away, Virginia Britton, 65, a ballet teacher and self-described “Red Rebel,” said she was dressed all in red to symbolize the blood of species facing extinction.

“It looks like George Floyd was extinguished,” she told Sharif Omar, 45, who stopped to ask her about her outfit.

After she walked away, Omar, who is African American, said the involvement of whites means “that people will listen.” But he worried aloud that they will “hijack the movement” and set the agenda.

“Whites help make other races understand what’s happening,” he said. “But they should not be leading.”

As the day wore on, crowds gathered on Capitol Hill, in Chinatown, on U Street, along the Mall and at Meridian Hill Park, where someone was offering free massages. Over at the World War II Memorial, 5-year-old Bella Sanders — “Dreamer” on the front of her T-shirt — twirled in the pool of water.

“Are you having fun?” Tyler Eichens, 16, asked.

“Yeah!” she answered.

The block-party atmosphere was not for everyone.

“This is a complete failure,” Marquell Washington, a 25-year-old Howard University student, said as he stood at the corner of 16th and K streets NW, go-go music playing from a nearby truck. “They stopped throwing tear gas and opened up the block a bit and now everybody thinks we won.”

“The saddest part is today could have been a day to send a message,” said his friend, Imran Sherefa. “We wasted it by dancing.”

A block over, at the corner of 16th and L streets, people stopped to take photos of a cluster of National Guardsmen standing around a military vehicle that blocked the road leading to the White House.

Keith Bakewell, a special agent with the Drug Enforcement Administration who volunteered to be on duty at the march, smiled as he greeted passersby. He hoped to “put a different face on law enforcement,” he said.

The past week, Bakewell said, “has been devastating for us.” He said that the video of police roughing up protesters “make the rest of us overly paranoid that we will do something that’s perceived as wrong.”

There were many people using their iPhones to chronicle the moment, asking strangers to pose with homemade signs that read, “American Swastika,” “Trump Mocks Christ” and “8 Minutes, 46 Seconds” — the amount of time that Chauvin kept his knee on Floyd’s neck.

As she watched the arriving crowd, Heather Jellison, 27, a math teacher from Prince William County, held a sign that read, “I’m not black but . . . I see you, I hear you, I stand with you.”

Jellison, who is white, said she felt that the country was undergoing a shift. A few years ago, when she went to a march in Pittsburgh for Trayvon Martin, an African American teenager who was killed in Florida in 2012, Jellison said she was among just a handful of whites in a crowd that was overwhelmingly black.

“There’s just so much more now, more people listening,” she said. But, she acknowledged “we have a long way to go.”

Nearby, John Brackett, 43, an African American massage therapist, wore a “Not Today Satan” T-shirt as he peered through the fencing surrounding Lafayette Square. He said he appreciated the white people in the crowd but he was distressed that there weren’t more black people.

He worries that impassioned speeches and marching is not enough to bring about change.

“It’s a little too kumbaya,” he said. “If you want real change, you need real action.”

A block away, on 16th Street, an African American man with a bullhorn shouted, “Get a fist up! Say it loud! I’m black and I’m proud!”

On cue, a crowd of fists shot up.

Hannah Natanson and Michael E. Miller contributed to this report.