The Claremont Institute has been located in Southern California since its founding in the late 1970s. From its perch in the foothills of the San Gabriel Mountains, it has become a leading intellectual center of the pro-Trump right.

Without fanfare, however, some of Claremont’s key figures have been leaving California to find ideologically friendlier climes. Ryan P. Williams, the think tank’s president, moved to a suburb in the Dallas-Fort Worth area in early April.

His friend and Claremont colleague Michael Anton — a California native who played a major role in 2016 to convince conservative intellectuals to vote for Mr. Trump — moved to the Dallas area two years ago. The institute’s vice president for operations and administration has moved there, too. Others are following. Mr. Williams opened a small office in another Dallas-Fort Worth suburb in May, and said he expects to shrink Claremont’s California headquarters.

“A lot of us share a sense that Christendom is unraveling,” said Skyler Kressin, 38, who is friendly with the Claremont leaders and shares many of their concerns. He left Southern California to move to Coeur d’Alene, Idaho, in 2020. “We need to be engaged, we need to be building.”

As Mr. Trump barrels through his third presidential campaign, his supporters buoyed by last week’s debate, many of the young activists and thinkers who have risen under his influence see themselves as part of a project that goes far beyond electoral politics. Rather, it is a movement to reclaim the values of Western civilization as they see it. Their ambitions paint a picture of the country they want should Mr. Trump return to the White House — one driven by their version of Christian values, with larger families and fewer immigrants. They foresee an aesthetic landscape to match, with more classical architecture and a revived conservative art movement and men wearing traditional suits.

Their vision includes stronger local leadership and a withered national “administrative state,” prompting them to celebrate last week when the Supreme Court effectively ended the “Chevron deference,” which could lead to the weakening of thousands of federal rules on the environment, worker protection and beyond.

Fed up by what they see as an increasingly hostile and disordered secular culture, many are moving to what they view as more welcoming states and regions, battling for American society from conservative “fortresses.”

Some see themselves as participants in and advocates for a “great sort,” a societal reordering in which conservatives and liberals naturally divide into more homogenous communities and areas. (And some, including Mr. Kressin, are simultaneously chasing the cheaper costs of living and safer neighborhoods that fuel many ordinary moves.)

The year Mr. Kressin moved to Idaho, he and Mr. Williams were part of an informal conversation at Claremont about the need for new institutions in what some hope will be a rejuvenated American society. The idea was a “fraternal community,” as one leader put it, that prioritized in-person meetings. The result was the all-male Society for American Civic Renewal, an invitation-only social organization reserved for Christians. The group has about 10 lodges in various states of development so far, with membership ranging between seven and several dozen people.

The group’s goals, according to leaders, include identifying “local elites” across the country and cultivating “potential appointees and hires for an aligned future regime” — by which they mean a second Trump presidency, but also a future they describe in sweeping and sometimes apocalyptic terms. Some warn of a coming societal breakdown that will require armed, right-minded citizens to restore order.

The group’s ties to Claremont gives it access to influence in a future Trump administration: Mr. Anton served on Mr. Trump’s National Security Council, and a Claremont board member, John Eastman, advised Mr. Trump’s 2020 election campaign. He faces criminal charges in Arizona and Georgia over schemes to keep Mr. Trump in power after he lost that race.

Their rhetoric can sound expansive to the point of opacity. “As the great men of the West bequeathed their deeds to us, so must we leave a legacy for our children,” the group’s website proclaims. “The works raised by our hands to this end will last long after we are buried.”

Their output, so far, looks more modest. Mr. Kressin’s home chapter has hosted an expert in menswear, who exhorted members to dress in a “classical American style,” and a screening and discussion of the 2003 naval adventure film “Master and Commander.” The men socialize outside of meetings and pass each other business.

The circle’s critics say they present a cleaned-up version of some of the darkest elements of the right, including a cultural homogeneity to the point of racism and an openness to using violence to achieve political ends.

“It’s this idea of organizing discontent at the local level and building a network that over the next decade or three decades or even half-century would just keep moving the Republican Party further and further rightward, and mobilizing voters in discontented parts of the country, a lot of them men,” said Damon Linker, a senior lecturer in political science at the University of Pennsylvania, who has written critically of the crowd. “It’s a highbrow version of the militia movement.”

In its first two years, leaders said, SACR received significant funding from Charles Haywood, a former business owner in Indiana. Mr. Haywood seems to delight in being an online provocateur. He has called the riot on Jan. 6, 2021, an “electoral justice protest” and praised the racist 1973 novel “The Camp of the Saints.”

Posting on the platform X last month, he wrote that foreign-born citizens should be deported for offenses including “working for Left causes.” Other leaders attribute the apocalyptic tone of the group’s founding documents to Mr. Haywood, who declined to comment.

Members of the society are young, mostly white-collar (and mostly white), and often wealthy. Some have left elite institutions to start their own firms and invest in conservative-leaning ventures.

Josh Abbotoy, the executive director of American Reformer, a Dallas-based journal that serves as an informal in-house publication for the movement, is moving to a small town outside Nashville this week with his wife and four children. Through his new professional network, he is raising funds to develop a corridor of conservative havens between Middle Tennessee and Western Kentucky, where he has also purchased hundreds of acres of property. He expects about 50 families to move to the Tennessee town — which he declined to identify — in the next year, including people who work from home for tech companies and other corporations.

Mr. Abbotoy is betting big on the revitalization of the rural South more broadly, as white-collar flexibility meets conservative disillusionment with liberal institutions and cities. He sees the Tennessee project as a “playbook” for future developments in which neighbors share conservative social values and enjoy, he suggested, a kind of ambient Christian culture.

“I personally would happily pay high H.O.A. fees to be in a neighborhood where I have to drive by an architecturally significant church every day, and I can hear church bells,” he said.

The Obergefell v. Hodges decision, which legalized same-sex marriage nationally, was a watershed moment for Mr. Abbotoy and other conservatives’ understanding of how quickly the ground could shift under their feet. It is a decision that signaled to them the onset of an era that the conservative Christian writer Aaron Renn — who has spoken at the fraternal society’s events — calls “negative world,” an influential concept that describes a culture in which “being known as a Christian is a social negative, particularly in the elite domains of ­society.”

Mr. Abbotoy was raised in an evangelical culture that encouraged conservative Christians to go out into “the world” and influence secular institutions, including corporations and universities. But that approach, which defined the last several generations of mainstream evangelicalism, feels increasingly untenable to people in his circle.

Mr. Abbotoy, who graduated from Harvard Law School, left a job with a major infrastructure company in 2021 and came to work for Nate Fischer, a Dallas venture capitalist and prolific networker whose firm invests in conservative projects and opposes “DEI/ESG and the bureaucratization of American business culture.” Mr. Fischer is the president of SACR’s Dallas chapter.

Andrew Beck, a brand consultant for conservative politicians and entities including SACR and Claremont, moved with his wife and their now six children, along with his parents and five of his siblings and their families, from Staten Island to suburbs north of Dallas in 2020. Almost 30 members of the family now live in the same area, just as they did in New York.

“Something is shifting that’s tectonic,” said Mr. Beck, who wrote a widely shared essay on “re-Christianizing America” for Claremont’s online magazine the American Mind. “It’s not so much about staking out some stronghold where you can live in a cocoon, it’s to be a part of a place you can truly consider to be home.”

Members must be male, belong to a “Trinitarian Christian” church, a broad category that includes Catholics and Protestants, but not members of the Church of Jesus Christ of Latter-day Saints. Members must also describe themselves as “unhyphenated Americans,” a reference to Theodore Roosevelt’s speech urging the full assimilation of immigrants.

The group’s interdenominational membership reflects the fact that in the Trump era, conservative Christianity is increasingly becoming a cultural and political identity, with theological differences falling to the wayside and Christianity serving as a kind of generic expression of rebellion against modernity. A significant minority of members are Catholic, including Mr. Kressin. The group also includes Presbyterians, Baptists and charismatics.

In Mr. Kressin’s new hometown in Idaho, the streets are clean and people leave their doors unlocked. His family lives in a house they can afford to own, with a white picket fence and room for a trampoline in the yard. In the cozy living room, an upright piano stands in the corner, and hymnals and classic novels line shelves on the wall.

“Many in our generation are very, very much longing for rootedness,” he said. “And they were raised in an era where that was really not valued very much.”

On a weekday morning this spring, he took a brisk morning stroll out his front door and up Tubbs Hill, with wildflowers sprinkled along the path and soaring views of the crystalline lake below. At his house afterward, Lauren Kressin, who was pregnant with the couple’s eighth child, served peach tea in tastefully mismatched china, quietly switching cups with him so he would have the “less feminine” one, she said with a smile.

Starting over in Idaho, Mr. Kressin said later, was part of a project so long term that he does not expect to see its conclusion. “The old landed aristocracy in England would plant oak trees that would only really mature in 400 years,” he said. “Who knows what the future holds, but if you don’t even start building a family culture, you’re doomed to fail.”