Why has U.S. politics became so rancid in tone and so harshly polarized?

Analysts have pinned the blame variously on talk radio and cable news, social media and the Internet, gerrymandering of U.S. House and state legislative districts, the Supreme Court’s campaign finance ruling, suspicion of authorities and cultural rebellion since the 1960s, a general coarsening of culture, economic woe, and much else.

Now comes prominent liberal analyst Peter Beinart with a striking thesis in the April issue of The Atlantic (which alongside its Web site has emerged as the most interesting source of religion coverage and commentary among general-interest magazine companies). He contends that what ails the fractured republic has much to do with the serious slide in church involvement over recent years.

His scenario deserves major media attention, with  responses from fellow pundits and Christian conservatives who will dislike his anti-Donald Trump slant and  resent any connection with the “race-and-nation” movement.

Beinart, who is Jewish, is an old-school New Republic editor turned journalism professor who writes for The Atlantic and others. He notes that some analysts welcomed the increase of “nones” who lack all religious affiliation, figuring this would foster greater tolerance and social harmony. Beinart’s view is precisely the opposite.

Yes, there’s more acceptance of gay marriages and legalized marijuana, he says. But the slide in organized religion is “making America’s partisan clashes more brutal” and contributes to the rise of the “alt-right,” and  “white nationalism,” pitting “us” against “them” in “even more primal and irreconcilable ways.” The older “culture war over religious morality” has been succeeded by a “more secular, more ferociously national and racial culture war” that is worse.

Beinart piles up survey research to back up that claim. For instance, the Public Religion Research Institute reports the percentage of white Republicans with no religious ties has nearly tripled since 1990. President Trump, who focused voter despair and resentment, did best with evangelicals who don’t attend church while weekly worshipers supported conservative candidates with different messages.

Surveys show “culturally conservative white Americans who are disengaged from church experience have less economic success and more family breakdown” and “grow more pessimistic and resentful.” White working class Americans without church involvement are more likely to suffer from divorce, addiction and financial distress. They share traditional aspirations about life but have trouble holding on to a job or a marriage “and otherwise forging real and abiding ties in their community.”

The bottom line: The worse they fare, the darker their view of their country.

Tolerance? Beinart says when cultural conservatives drop out of organized religion, they grow more hostile toward African Americans, Latinos and Muslims. Even hard-shell conservative churchgoers are continually taught to love thy neighbor. But “when cultural conservatives disengage from organized religion, they tend to redraw the lines of identity, deemphasizing morality and religion and emphasizing race and nation.” He sees President Trump as “both a beneficiary and a driver of that shift.”

Beinart sees effects beyond white Protestantism. Religious “nones” helped fuel the successes of the very secular Bernie Sanders’s insurgency against Hillary Clinton and the Democratic establishment. Likewise with “Black Lives Matter,” which is far more disengaged from religionthan the older civil rights movement, and oriented more toward fueling resentments than achieving multi-racial reform.

The upshot: Whatever the ways religious involvement creates positive social effects, we find that “secularization isn’t easing political conflict. It’s making American politics even more convulsive.” And with “post-Christian” perspectives on the rise, “it’s easy to imagine American politics becoming more and more vicious.”