DALLAS >> Two months after this city’s darkest day in November 1963, when President John F. Kennedy was killed by a sniper in Dealey Plaza, James F. Chambers, publisher of The Dallas Times Herald, was ordered out of a cab in the Detroit snow. He had made the mistake of telling the driver he was from Dallas.

For years after the assassination, Dallas was labeled the “city of hate” because it had been the focal point of a loose-knit, anti-Kennedy movement led by right-wing extremists. The city’s response was, for the most part, silence. It stepped, for a time, into the shadows of the national stage because of its guilt, shame and anger, growing only more insular and misunderstood.

Fifty-two years later, the second-worst day in the city’s history has provided Dallas with a new and dramatic global moment. It has seized that moment far differently, presenting to the nation the face of a majority-minority city with diverse, grace-under-pressure leaders and a calm efficiency in the face of chaos. And when President Barack Obama and former President George W. Bush — one a black Democrat, the other a white Republican — led a memorial service Tuesday in honor of the five police officers killed last week, it cast Dallas as something of a national model in an agitated time, a place that managed to turn down the temperature in a nation nearing a boiling point.

In truth, the moment reflected both a new, more diverse and tolerant Dallas and an old pragmatic, consensus-oriented one. For example, Dallas integrated its schools peacefully in 1961, without the chaos common across the South. Its powerful business community sent out the word that calm was better for business than disorder. But this week it was that new Dallas, not the old one, that seemed most apparent.

“Thursday changed the way the world is going to view Dallas,” said Carol Reed, a longtime political strategist here. “In ‘63, we were having discussions on ‘Are we really a people that hate?’ Now, we’re probably setting the tone for how we should discuss race in America, policing in America. The stereotype of us being a bunch of yahoos down here — with the Cowboys and the big hair — was broken on Thursday night, or broken in the days that followed.”

Not that Dallas, a place defined in large part by its divisions, is any sort of racial nirvana. In the city core, a black-white split remains, with many blacks living south of Interstate 30 as in decades past, and whites north of it. The north is generally wealthy, the south generally not.

There is also a generational divide, as younger leaders gain political power and clash occasionally with the older, more traditional establishment. And beyond the city, Dallas, itself, tends to be more liberal, and the suburbs surrounding it more conservative. And yet those suburbs have become increasingly international while also becoming increasingly friendly to Tea Party politics.

These deeply embedded historical divisions did not vanish overnight after the Dallas shooting. But they seemed a little less rigid, as the city’s white mayor, white county executive, black police chief, Latino city manager and Latina lesbian sheriff have projected a striking image of modern, melting-pot Dallas. And they have done so in a place that was once considered perhaps the most conservative big city in the country, dominated by the corporate chieftains of the Dallas Citizens Council and where, 92 years ago in October 1923, the flagship annual event, the State Fair of Texas, celebrated Ku Klux Klan Day.

“I find myself,” said Jim Schutze, a columnist at the alternative newspaper The Dallas Observer who has long been a critic of Dallas’ powers that be, “with this eerie, unaccustomed optimism.”

When Krista Nightengale, 31, first came to Dallas, she thought she would stay for a year or two before moving on to a city with a more national reputation for attracting young talent, a New York or a San Francisco, maybe. That was nine years ago.

Nightengale is part of an emerging urban subset of the city — hip, progressive and civic minded — that has injected a new, vibrant energy here. The same forces are at work in Nashville, Atlanta, Houston and other parts of the Sun Belt. In cities once known for white privilege and exclusivity, the newcomers are clamoring for inclusion. In a metropolis where the freeway has long been viewed as vital, they are clamoring for walkable streets and neighborhoods.

Nightengale, who is white, is among thousands of people who now live downtown, an area where there was once very little residential life and that now boasts a small streetcar system. Many other millennials reside in Oak Cliff, the area where Lee Harvey Oswald lived and was arrested after the assassination — now full of hip restaurants and hangouts. Nightengale, a former managing editor of D Magazine, works for the Better Block, a nonprofit group that supports urban revitalization and is involved with a movement that wants to tear down Interstate 345 and replace it with boulevards and businesses.

“They only know ‘Who Shot J.R.’” she said, referring to the famous cliffhanger plotline from the 1980s TV show that bore the city’s name. “And we’re so far beyond that. We’ve made so many strides. I don’t think people understand that yet.”

But even as Dallas has appeared united and renewed, some argue that this depiction is a distortion of the city and its troubles.

“It’s probably not unlike any other city in America,” said John Wiley Price, a Dallas County commissioner who is black. “I know they want to tout the statistics and they want to talk, but it’s still a tale of two cities. I think they’ve been able to put the lipstick on.”

Price is among the most controversial politicians here. A federal grand jury indicted him almost two years ago in a corruption case. In that case, which is pending, Price is accused of taking nearly $1 million in cash, land and vehicles in a bribery scheme. He has pleaded not guilty.

Price, who remains in office, argued that the city’s southern neighborhoods received nowhere near sufficient resources and attention from officials.

“Just because the John Birch Society is no longer hanging out their shingles, just because they want to call the White Citizens Council the Citizens Council and maybe put an African-American on the staff, nothing institutionally has changed in this city,” Price said. “And it shows.”

Price and other black leaders said it was unclear how, and if, the response to the Dallas shootings will change an issue that Dallas has grappled with for decades — the degree to which it remains segregated.

In the 1980s, community advocates sued the Dallas Housing Authority and the U.S. Department of Housing and Urban Development for discriminatory housing. The parties had reached a settlement in 1987 that would provide vouchers allowing low-income families to move wherever they wanted to. But the city of Dallas obstructed the settlement, and so the advocates sued the city, resulting in a U.S. District Court decision in Walker v. HUD that found that Dallas was violating the law and that vouchers had to be provided.

Separately, a federal court ruled in 2012 that the city’s housing policies discriminated against black residents, and a different federal investigation determined in 2013 that Dallas officials had worked to maintain housing segregation.

“You can have all the enlightened training you want for the police,” said Craig Flournoy, a former investigative reporter for The Dallas Morning News who is now chairman of the Inclusive Communities Project, a local nonprofit group that promotes integrated, affordable housing. “You can try to go into the schools and tell young black men that the police are their friend, not their enemy. But until we do something about racial segregation and housing in the city, nothing is fundamentally going to change. That’s as true, of course, in Dallas as it is in Baton Rouge, in Minneapolis and any other major city in the country.”

Still, Miguel Solis, 30, a member of the Dallas school board, embodies some of the changes the city has seen in recent years. Solis came to Dallas in 2009 and was elected to the board in 2013. Though about 70 percent of the 160,000 students in the Dallas Independent School District are Hispanic, he said there were no Hispanic board members when he ran for a seat on the board. Now, three years later, the board has three Hispanics, three blacks and three whites.

“Dallas has significantly changed, and it will continue to significantly change because the demographics are significantly changing,” he said.

Solis was in Cambridge, Massachusetts, for a conference recently, before the shootings. When he told people where he was from, he said, they did not want to know about the Cowboys or who shot J.R. They were interested in the way the city handled the Ebola crisis in 2014.

“It was, ‘Tell us about how you guys led the nation on an epidemic that we’ve never faced in our land,’” Solis said about those at the conference. “And I’ll bet if I went back to Cambridge in a couple of months, they’d want to know how we faced this issue as well. We have had miserable times in Dallas. And at every one of those miserable times, we could have stopped and let the misery define us, but we don’t. We persevere.”

© 2016 The New York Times Company