It’s been more than six months since the clouds of tear gas dissipated from her West Philadelphia block, but the terror of running from police as they shot her neighbors with rubber bullets is still fresh in Amelia Carter’s mind.

As she watched from a livestream as hundreds of mostly white, pro-Trump insurrectionists stormed the Capitol building in Washington on Wednesday, the contrast hit Carter cold.

The police were running from them.

Over the summer in Philadelphia and across the country, record crowds protested and raged against police killings of Black people and for an end to systemic racism, and in many cases were met with tear gas, armored vehicles, baton-wielding riot cops, and mass arrests.

And so racial justice activists watched in horror but not surprise as loyalists of President Donald Trump destabilized the transition of power in the name of radical fantasies of a stolen election pushed by the president himself. Footage showed the armed mob inside the Capitol for four hours, some taking selfies with police and looting congressional offices, others exiting the building free and unscathed.

One video showed police moving away from barricades, allowing crowds to spill through toward the Capitol. Another showed an officer holding a rioter’s hand, walking her down the Capitol steps.

“The difference between these cases is that those people were Black and living in a predominantly Black neighborhood, or were white folk who were participating in antiracist activism,” said Carter, an organizer with Penn Community for Justice and a plaintiff in a lawsuit against Philadelphia police for their actions on 52nd Street in May. “This really was a very dramatic and clear example of the white supremacy that’s embedded in policing.”

Lawmakers from City Council to the president-elect this week contrasted the police responses while Americans filled Instagram stories and Twitter feeds with images of Black Lives Matter protesters brutalized by officers.

Local activists said they were reminded of how officers last summer stood by as mobs of armed, white men patrolled Philadelphia neighborhoods, hurling racist slurs and assaulting people. In Fishtown on June 1, a group of men with bats roamed for hours after curfew, the same day police fired tear gas at Black Lives Matter protesters who were trapped in a ravine along I-676.

Weeks later, a crowd of more than 100 people, many donning pro-Trump gear, claimed to be protecting a Christopher Columbus statue in South Philadelphia and ran toward racial justice activists who had marched there. A member of the mob punched Mel D. Cole, a professional photographer from New York, in the face.

Cole, who is Black, spent last year documenting protests after a Minneapolis officer killed George Floyd by kneeling on his neck as he gasped “I can’t breathe.”

And he was in Washington on Wednesday standing with his camera behind yet another pro-Trump mob. He watched as police retreated from the Capitol steps, allowing the insurrectionists to advance.

When police reinforcements arrived and sprayed chemical irritants at the rioters, Cole said, members of the crowd called police “traitors.”

Then they began chanting: “I can’t breathe.”

President-elect Joe Biden said in an address to the nation Thursday that his granddaughter Finnegan, a senior at the University of Pennsylvania, sent him a text message Wednesday with a picture that showed scores of military personnel lining the steps of the Lincoln Memorial during a Black Lives Matter protest.

”No one can tell me that if it had been a group of Black Lives Matter protesting yesterday, they wouldn’t have been treated very, very differently,” Biden said.

Police deployed tear gas inside the Capitol Rotunda, and officers fatally shot a woman. More than 50 officers were injured, and one died. But Capitol Police have been roundly criticized for appearing ill-prepared — despite the president directing the crowd to go to the Capitol — and allowing the mob to burst inside.

Walter Katz, vice president of criminal justice at Arnold Ventures, a progressive philanthropy and research organization, said Wednesday’s response at the Capitol should be studied “from top to bottom.” But he also said law enforcement needs to examine why the opposite was true for demonstrations across the country demanding police reform.

While Philadelphia police officials said the force was initially unprepared for the demonstrations and struggled to control crowds, they later came equipped with large numbers of officers and heavy-duty equipment.

”What this is the opportunity for us to take these questions of implicit bias beyond decision-making by the individual officers, but also to understand how police organizations make decisions in assessing demonstrations,” Katz said, saying law enforcement needed to examine “the core of how [they] assess a threat in the first place.”

In addition to the unpreparedness, the response remained tame as many who stormed the Capitol left the building. Police in Washington reported a preliminary total of 69 arrests Wednesday, and most were accused of violating the city’s 6 p.m. curfew. U.S. Capitol Police made 14 arrests; 11 were charged with unlawfully entering the Capitol.

Between May 30 and June 4 of last year, when Black Lives Matter protests gripped the nation, D.C. Metropolitan Police reported 427 arrests for curfew violations, burglaries, and other “riot-related events,” according to the department. On June 1, when Trump wanted to take a photo in front of St. John’s Church, U.S. Park Police teargassed a crowd of peaceful demonstrators in Lafayette Park to clear the way.

“We love you, you’re very special. ... I know how you feel, but go home, and go in peace.”

“Nobody came close to breaching the fence. If they had, they would have been greeted with the most vicious dogs, and most ominous weapons, I have ever seen.”

In Philadelphia in the days following Floyd’s killing, police reported 226 protest-related arrests and issued another 490 citations for violations like failing to disperse and violating curfews.

The department itself was criticized for contributing to the chaos: Two officers ended up charged with assaulting demonstrators — one with a baton, another with pepper spray. And in addition to officers indiscriminately firing tear gas along the 52nd Street corridor, Philadelphia police turned I-676 into a tornado of tear gas.

It was sunny on June 1 as Xavier Wofford stood with protesters on 676 chanting “hands up, don’t shoot.” Then, Pennsylvania State Police officers fired rubber bullets at them. He said he was hit eight times, inundated with tear gas, blacked out, and had a seizure.

Watching a mob storm the U.S. Capitol and largely leave unscathed, he said, triggered symptoms of post-traumatic stress disorder.

“I helped lead a peaceful protest and I watched thousands of people get assaulted and violently attacked,” Wofford, 25, of Philadelphia, said. “But they can storm the Capitol with guns and nothing happens. ... It was a spit in our face.”

Tyler Shaide, 24, was alongside Wofford as the group moved onto the highway. Shaide said he took tear gas and was shot by rubber bullets. He can’t bring himself to go back to that spot on the highway.

”If they were Black, that would have been a massacre,” Shaide, who is Black, said of what he watched Wednesday.

In addition to the treatment of protesters, racial justice demonstrators were in many cases greeted by police in riot gear, while Capitol Police on Wednesday initially donned their everyday blues.

In October, after Philadelphia police fatally shot Walter Wallace Jr., more than a thousand National Guard members were on standby for a week in preparation for unrest over the release of body-worn camera footage. No one in fatigues carrying a long gun appeared to be guarding the Capitol.

“No matter how wrong these folks are or were, they get the benefit of being white,” said Abdul-Aliy Muhammad, cofounder of the Philadelphia-based Black and Brown Workers Cooperative.

Activists called out the discrepancy in the police response far beyond Philadelphia. Police across the country used heavy-handed tactics against anti-police-brutality protesters last year, from federal officers who threw Portland demonstrators into unmarked vehicles, to police in New York who beat protesters with batons.

Steve Young, an Atlantic City activist who led several Black Lives Matter protests, said the contrast was bitterly obvious.

”We would have been shot dead,” he said, “and you’d have had to have a candlelight vigil because we were Black.”

Paul Hetznecker, a Center City defense lawyer who has frequently represented protesters, including more than 140 people who demonstrated last summer, said if people storming the Capitol had been aligned with Black Lives Matter or a similar group, “they would’ve been demonized, they would’ve been locked up, they would’ve been charged federally as a threat to national security.”

He called the uneven treatment “a threat to our democracy,” and said it must be part of discussions around criminal justice reform.

Krystal Strong, an organizer with Black Lives Matter Philadelphia and professor at the University of Pennsylvania, advocates for defunding and abolishing the police. She said recent quibbling over the effectiveness of the “defund the police” mantra detracts from the issue: “white supremacist violence... aided and supported and by the police.”

“These contradictions,” she said of Wednesday’s insurrection, “require us to let go of some of these fictions that the system can repair itself.”

Philadelphia City Councilmember Kendra Brooks, a member of the progressive Working Families Party who has been critical of the police response to protests, said the response to the insurrection at the Capitol further solidifies the need to overhaul the public safety system in favor of a community-based model.

“The Black Lives Matter protests were immediately met with violence,” she said. “And violence by white folks was met with grace.”

While people on both sides of the aisle expressed shock at the treatment of the insurrectionists, Brooks said Wednesday was just another example of her long-held conviction that American institutions are rooted in anti-Blackness.

“It just brings me to the reality that I’ve known my whole life,” she said, “which is that this system that we have will not protect my Black body or my children.”

Staff writer Amy S. Rosenberg contributed to this article.