A video clip of Ronald Reagan and George H.W. Bush answering questions about immigration at a 1980 debate is making the social media rounds, drawing attention not just for what would be considered moderate positions on immigration today, but for the generous and respectful tone of the candidates to one another.

Fast-forward 26 years to the March 4, 2016, Republican primary debate, a round-robin of insults in which candidates Marco Rubio and Ted Cruz engaged in increasingly hostile personal attacks on front-runner Donald Trump. Trump in turn referred derisively to them as “little Marco” and “lying Ted” and tossed in an allusion to his own private parts.

Many observers, including 2012 Republican nominee Mitt Romney, blame Trump’s penchant for profanity and name-calling for the tenor of this year’s campaign. But in spite of efforts to call him out for immature behavior, Trump ’s divisive rhetoric is resonating with a set of Americans who continue to propel him to primary victories in state after state.

Trump may be riding a wave of polarization and antipathy, but he didn’t create it. Experts say the last 50 years have given rise to several trends — including the end of the Cold War, rule changes in Congress, the proliferation of partisan media outlets, immigration patterns and urban-rural divides — that are converging in a perfect storm of hyper-partisanship and tribalism.

Americans are more divided along ideological lines than at any point in the past two decades, the Pew Research Center reported in 2014, and partisan hostility runs deeper than ever.

As people sort themselves into tribes based on everything from neighborhoods to news outlets, a small group of activists and academics is taking note and searching for ways to stem the partisan tide. They’re organizing events, writing books and recruiting people to engage in face-to-face dialogue with others of radically differing viewpoints.

Some believe there could be a movement toward depolarization; others aren’t sure. But all agree that the skills of compromise and statesmanship will be essential to the future functioning of American government, and they want as many people as possible to gain them.

“There is no enduring way for citizens to advance their own values without working with others,” said Mark Gerzon, 66, an author and leadership expert who designed bipartisan retreats for members of Congress in the 1990s.

“Anyone who is married knows it can be hard. If we want to be a democracy, not a dictatorship, we have to work with people different from ourselves."

The path to polarization

Sarah Jordan is an adult ESL teacher in the Glendale neighborhood of west Salt Lake City with a self-described passion for social justice. Immigration is a live issue for her students, many of whom come from mixed-status families, and she’s distressed by Trump’s polarizing rhetoric about immigrants, she says.

It’s a cold night in February, and Jordan, 53, is sitting next to Derek Monson, director of public policy at the conservative Sutherland Institute think tank, at a table in the local community center. They both came to talk about immigration at an event sponsored by The Village Square, an organization that aims to facilitate conversations between people who disagree, sometimes intensely.

They take turns talking about what they believe is at the heart of the immigration debate, and Jordan leans back stiffly in her chair, avoiding eye contact with Monson.

It’s increasingly rare to find people like Monson and Jordan conversing at all on political topics, in part because they so rarely cross paths anymore. Americans are increasingly self-segregating into neighborhoods based on their political ideology, documented in journalist Bill Bishop’s book “The Big Sort: Why the Clustering of Like-Minded America is Tearing Us Apart.”

One in four Americans have unfriended someone on Facebook for having different politics, according to the Pew Research Center, and another recent Pew study found that more Americans would be upset about their child marrying someone of another political party than if they married another race.

This isn’t the first time Americans have been intensely polarized, said David Blankenhorn, founder of the Institute for American Values, a New York-based think tank. The years leading up to the Civil War were particularly polarizing, as were the 1890s, when there were fights over farmers’ debt, and the 1960s, when people were polarized over Vietnam.

“The difference between then and now is that in most other periods, polarization tended to be around one or two issues. Now almost all of the issues are polarized,” he said.

The other difference now, he said, is that people have so little connection to those they disagree with.

“You sign up to be on one team or the other, and each team has its own positions on every single issue,” he said. “So if somebody says to you, ‘Today’s Thursday,’ and that person’s from the other party, you’re going to say, ‘Well, we’ll see about that.’”

Polarization leads to harmful intellectual habits such as black-and-white thinking, Blankenhorn said. It encourages people to view uncertainty as weakness, to assume opponents are motivated by bad faith, and to hesitate to agree on basic facts — which in turn fosters more polarization.

A new movement?

Trump’s comments are driving interest in events like the Village Square one in Salt Lake that bring together people on different sides of political issues, said Jacob Hess, director of the Salt Lake chapter of The Village Square.

The group was founded in Tallahassee a decade ago and is expanding into other states, including Utah, where it is working in partnership with Living Room Conversations, a national organization that helps people facilitate self-guided conversations in their own homes and neighborhoods with people of differing viewpoints. Hess hopes efforts like The Village Square are having a moment, but said he’s under no illusions it’s about to take the country by storm.

Other groups are also popping up. One of them is Blankenhorn’s new project, Better Angels, born of his own bitter experience in the public eye first as an opponent of gay marriage — he testified in the Proposition 8 case in California in 2010 — and later as a supporter.

Having been “clobbered” by people on both sides of that rancorous issue, Blankenhorn said he realized that polarization wasn’t simply a phenomenon that occurred on particular issues, but an issue of its own that needed to be addressed head-on.

Better Angels has a three-year plan that includes sponsoring research on “depolarization indicators” — such as feelings and opinions Americans have about members of opposing political parties — and hopes to enlist a significant fraction of the population to be trained in political dialogue and planted in local communities.

Like Hess, Blankenhorn was hesitant to say he’s part of a groundswell movement to depolarize the country.

Gerzon, however, believes a movement could be forming, and he uses the word “transpartisan” to describe it. His new book released last month, “The Reunited States of America: How We Can Bridge the Partisan Divide,” highlights the efforts of those working to help the country be less polarized.

Gerzon said polls provide clues to the potential size of the movement by tracking the high number of people who identify as independents. Recent Pew Research Center data show independents make up 40 percent of Americans, an all-time high that makes the number of independents larger than either Republicans or Democrats.

“It’s not that they don’t have liberal or conservative leanings, it’s just that they don’t think it’s constructive to add weight to the right or the left,” Gerzon said.

Gerzon also noted that the movement isn’t new and that people have been trying to bridge the partisan gap for decades.

The National Coalition for Dialogue and Deliberation was founded in 2002 as a network of people interested in fostering understanding between different groups in a variety of fields. It serves as a clearinghouse for information and is one of the leading organizations in the dialogue movement.

NCDD built on the success of the Public Conversations Project, started 27 years ago by Laura Chasin, a marriage and family therapist who realized that the same skills she was teaching families in therapy could help Americans debating political issues.

Changing hearts, not minds

Some people like polarization because it gives them a sense of security and superiority, Hess said.

“If (polarization) wasn’t a winning political strategy, if it didn’t appeal to deep human needs and feelings, we wouldn’t have it,” Blankenhorn said.

So far, liberals seem more interested than conservatives in depolarization groups and events, Hess said. It may be that the whole concept of dialogue sounds too progressive, he said, and he is working on ideas to engage the city’s religious community more deeply.

Gerzon said his biggest skeptics are his friends on the far left and the far right who believe in conspiracy theories and accuse him of “singing Kumbaya in a war zone.”

There may be some truth in that, he said, but having worked as a U.N. mediator in countries including Nepal and Kenya, he has learned that “when the middle disappears — when you talk yourself out of there being a middle — you have violence.”

Hess is adamant that changing minds isn’t the goal of dialogue — it’s to recognize the humanity and the reasonableness of people on the other side.

Hess, a lifelong religious conservative, teamed up with Phil Neisser, an atheist, Marxist professor at State University of New York, to write a 2012 book called “You’re Not as Crazy as I Thought … But You’re Still Wrong” in which the authors converse on topics from big government to race and sexuality.

Hess and Neisser still strongly disagree politically, but writing the book was “transformative,” Hess said, and they became dear friends.

“(Talking about differences) changes you,” Hess said.

Hess also tells about a Living Room Conversation activity between three conservative Mormons and three members of the LGBT community. No one was converted to the others’ way of thinking, he said, but afterwards they were hugging and exchanging phone numbers.

“It’s more of a change of heart than a change of mind,” he said. “It’s like in a marriage. The turning point is often to accept that person is who they are and not try to change them, not force them or fix them."

Gerzon encourages people to take a 30-day “transpartisan vacation” in which they put aside their regular reading and activities and substitute things from the other side.

“Whatever you’re used to doing, take a vacation and read something different. Hang out with different people. Spend time at an event. If you always read the Times, read the Wall Street Journal,” he said. “See if you can come back with something of value.”

Other resources help people create their own dialogues. For example, NYU professor Jonathan Haidt founded the Asteroids Club, in which members of different political persuasions each identify what they believe is the No. 1 most dangerous problem, or asteroid, hurtling toward the country, and then commit to help each other deflect their asteroids.

Living Room Conversations and Jeffersonian dinners supply templates for inviting a group into your home to talk about typically polarizing issues.

Finding air

As the Salt Lake Village Square event wraps up, ESL teacher Jordan admits she was uncomfortable when she learned she was sharing a table with someone from the Sutherland Institute. But she was surprised to agree with Monson on several points.

“When he started talking about following the Constitution, I inwardly groaned. But then when he talked about the heart of the matter being about the individual person, I agreed,” she says. “And I love that.”

“I seek in my life to challenge my own beliefs. But I also am aware that sometimes I can hold my beliefs very tightly, and I love those moments when I find air,” Jordan says as Lee Greenwood’s “Proud to be an American” plays in the background.

Monson interrupts to say farewell as he heads for the door, and their exchange reflects an openness that wasn’t there before.

“It was great to chat with you,” he says.

“It was wonderful — and I like your tie,” Jordan replies.