"Liberalism now functions for a substantial number of adherents like a religion: an encompassing worldview that answers the big questions about life, lends significance to our daily exertions, and provides a rationale for meaningful collective action," Stanley Kurtz wrote in a 2001 piece for National Review, "The Church of the Left."
Now it's turning out that politics is substituting for organized religion on the right, too. NPR's "On Point" program has an interview with Michael Graham and Pastor Jim Davis, authors of The Great Dechurching. From the transcript:
Davis:...dechurching is happening on the secular right at twice the pace, almost catching up in the full number of those who have dechurched on the secular left.
Graham: ...Wouldn't you rather go to a political rally where you feel like maybe you have more solidarity, from either a civilizational level, ethnic level, or in terms of just the constellation of wants and fears that you have. So I think in many ways, we've experienced from 2015 to present an apocalyptic event, in the sense of the revealing of where people are really at.
The NPR host mentions this New York Times piece by my former New York Sun colleague Ruth Graham:
Religion scholars, drawing on a growing body of data, suggest another explanation: Evangelicals are not exactly who they used to be.
Being evangelical once suggested regular church attendance, a focus on salvation and conversion and strongly held views on specific issues such as abortion. Today, it is as often used to describe a cultural and political identity: one in which Christians are considered a persecuted minority, traditional institutions are viewed skeptically and Mr. Trump looms large.
"Politics has become the master identity," said Ryan Burge, an associate professor of political science at Eastern Illinois University and a Baptist pastor....
In 2008, over half of Republicans reported attending church at least once a month, according to data Mr. Burge compiled from the Cooperative Election Study at Harvard University. In 2022, over half reported attending church once a year or less....
An increasing number of people in many of the most zealously Trump-supporting parts of Iowa fit a religious profile similar to the former president's. "Iowa is culturally conservative, non-practicing Christians at this point," Mr. Burge said. "That's exactly Trump's base."
Pew also has a new report out on the religious "nones" that somewhat supports this idea and includes a round of recent data on religious service attendance. It says 29 percent of all U.S. adults attend religious services "monthly or more" and 56 percent attend "seldom or never." Gallup also has historical data on this:

Some of this may be pandemic related—some people stopped going to church during the pandemic and never went back. But a lot of the trends seem to predate it. Anyway, the insight that politics is now substituting for religion on the right in addition to on the left is big idea with a lot of implications and, potentially, explanatory power. It is worth keeping in mind.