The turbulence that followed the Nov. 3 election has roiled American politics, demonstrating an ominous vulnerability in our political system.

Donald Trump used the 41-day window between the presidential election and the Dec. 14 meeting of the Electoral College to hold the country in thrall based on his refusal to acknowledge Joe Biden’s victory and his own defeat.

Most troubling to those who opposed Trump, and even to some who backed him, was the capitulation by Republicans in the House and Senate. It took six weeks from Election Day for Mitch McConnell, the Senate majority leader, to acknowledge on Tuesday that “The Electoral College has spoken. Today I want to congratulate President-elect Joe Biden.”

Trump’s refusal to abide by election law was widely viewed as conveying an implicit threat of force. Equally alarming, Trump, with no justification, focused his claims of voter fraud on cities with large African-American populations in big urban counties, including Detroit in Wayne County, Milwaukee in Milwaukee County, Philadelphia in Philadelphia County and Atlanta in Fulton County.

Bob Bauer, a senior legal adviser to the Biden campaign, told reporters that the Trump campaign’s “targeting of the African-American community is not subtle. It is extraordinary,” before adding, “It’s quite remarkable how brazen it is.”

Viewing recent events through a Trump prism may be too restrictive to capture the economic, social and cultural turmoil that has grown more corrosive in recent years.

On Oct. 30, a group of 15 eminent scholars (several of whom I also got a chance to talk to) published an essay — “Political Sectarianism in America” — arguing that the antagonism between left and right has become so intense that words and phrases like “affective polarization” and “tribalism” were no longer sufficient to capture the level of partisan hostility.

“The severity of political conflict has grown increasingly divorced from the magnitude of policy disagreement,” the authors write, requiring the development of “a superordinate construct, political sectarianism — the tendency to adopt a moralized identification with one political group and against another.”

Political sectarianism, they argue,

consists of three core ingredients: othering — the tendency to view opposing partisans as essentially different or alien to oneself; aversion — the tendency to dislike and distrust opposing partisans; and moralization — the tendency to view opposing partisans as iniquitous. It is the confluence of these ingredients that makes sectarianism so corrosive in the political sphere.

There are multiple adverse outcomes that result from political sectarianism, according to the authors. It “incentivizes politicians to adopt antidemocratic tactics when pursuing electoral or political victories” since their supporters will justify such norm violation because “the consequences of having the vile opposition win the election are catastrophic.”

Political sectarianism also legitimates

a willingness to inflict collateral damage in pursuit of political goals and to view copartisans who compromise as apostates. As political sectarianism has surged in recent years, so too has support for violent tactics.

In a parallel line of analysis, Jack Goldstone, a professor of public policy at George Mason University, and Peter Turchin, a professor of ecology and evolutionary biology at the University of Connecticut, contend that a combination of economic and demographic trends point to growing political upheaval. Events of the last six weeks have lent credibility to their research: On Sept. 10, they published an essay, “Welcome To The ‘Turbulent Twenties,’ ” making the case that the United States is “heading toward the highest level of vulnerability to political crisis seen in this country in over a hundred years.” There is, they wrote, “plenty of dangerous tinder piled up, and any spark could generate an inferno.”

Goldstone and Turchin do not believe that doomsday is inevitable. They cite previous examples of countries reversing downward trends, including the United States during the Great Depression:

To be sure, the path back to a strong, united and inclusive America will not be easy or short. But a clear pathway does exist, involving a shift of leadership, a focus on compromise and responding to the world as it is, rather than trying desperately to hang on to or restore a bygone era.

The Goldstone-Turchin argument is based on a measure called a “political stress indicator,” developed by Goldstone in his 1991 book, “Revolution and Rebellion in the Early Modern World.” According to Goldstone, the measure “predicted the 1640s Puritan Revolution, the French Revolution of 1789, and the European Revolutions of 1830 and 1848.”

Goldstone wrote that

popular mobilization is more likely when the population is experiencing declining material conditions, plus urbanization and youth; when social competition for elite positions become heightened, political polarization and factionalism will be more likely as groups struggle for power and positions; and when state expenses fall behind revenues, as states become less capable of meeting expected demands and thus less legitimate, as well as more likely to enter conflicts with elites over taxation. And I argued that only when all of these factors coincide does a state face rising risks of major upheavals.

Turchin, in a 2017 book, “Ages of Discord: A Structural-Demographic Analysis of American History,” graphed political stress in this country, showing that from 1970 to 2012 it shot up sharply, increasing 40-fold. In the eight years since then, stress has continued to surge, Goldstone wrote, “as income inequality, political polarization and state debt have all risen further.”

While the United States is particularly vulnerable to violent upheaval, Turchin argues, a disaster “is not foreordained. On the contrary, we may be the first society that is capable of perceiving, if dimly, the deep structural forces pushing us to the brink.”

In congressional testimony earlier this year, Christopher Wray, the director of the F.B.I., warned of the dangers posed by white extremists. Take, for example, the largely unprintable postings on thedonaldwin — one of the more extreme right wing pro-Trump websites — on Dec. 11, the day the Supreme Court rejected 9-0 the Texas Attorney General’s attempt to invalidate Biden’s victories in Michigan, Wisconsin, Pennsylvania and Georgia. The pro-Trump participants used their anonymous internet pseudonyms to voice outrage that swiftly turned into extraordinary levels of frustration and rage at a Republican elite that they claimed had failed to protect their leader:

A poster whose name cannot be printed in this newspaper declared, “I can’t wait to taste your blood.” MakeLiberalsCryAgain put the case bluntly:

It’s INSANE. Many of these contested states have REPUBLICAN majorities in their legislatures. They had the power all along to stop this, and they haven’t done blankety blank. They held hearings to give the appearance of caring, but in the end, they all cucked out like the spineless, traitorous cowards they are. It looks like the uniparty is reality. What’s the point in voting when they’re all the same?

Even more explicit, dinosaurguy declared,“War it is,” joined by AngliaMercia, “We kill now.” Chipitin warned: “Never forget those justices were handpicked by McConnell and the Federalist Society. They told him they’ll help him out picking the best — only to make sure they’ll pick those that will betray him. Time to go to war with the Republican Party.”

These views on the hard right are not isolated. At the pro-Trump rally in Washington on Dec. 12, the day after the Supreme Court decision, the crowd chanted “Destroy the G.O.P.” at the urging of Nick Fuentes, a far right opponent of immigration.

Gary Jacobson, professor emeritus of political science at the University of California-San Diego, told me that the current upheaval on the right is “quite dangerous if the myth that the election was stolen from Trump persists at the current level among ordinary Republicans and is refuted by so few Republicans in Congress.”

Sectarianism, Jacobson continued in an email,

feeds on itself; it is exacerbated by the ideologically fragmented media environment. It also reflects real differences in beliefs and values and conceptions of what American is, or should be, all about. Cleavages of race, region, education, religion, occupation, and community type now put people more consistently on one side or the other, feeding the culture wars and aggravating negative partisanship.

Compounding the problem, Jacobson argues, is the fact that

grievances on both sides have a real basis — e.g., the economic and social decay of small town and rural communities for Trump supporters, systematic racism besetting minorities who vote Democratic — but there is no simple symmetry. For example, whites who believe they suffer more discrimination or fewer opportunities than Black and other minorities are for one reason or another simply oblivious to reality.

Eli Finkel, a professor of psychology at Northwestern and the first author of the paper on political sectarianism paper I started with, contended in an email that “if we consider Trump’s efforts in isolation, I am not especially concerned,” because the failure of his attempts to overturn the election so far have “provided a crucial and unprecedented stress test of our electoral system.”

If, however, “we consider the support for Trump’s efforts from officials and the rank-and-file in the Republican Party, I am profoundly concerned,” Finkel continued,

The foremost political story of the Trump era is not that a person like Trump could be so shamelessly self-dealing, but that Republicans have exhibited such fealty along the way, including a willingness to cripple the founding document they claim to view as sacrosanct.

Political sectarianism, Finkel concluded,

has now grown so severe that it functions as the most serious threat to our political system since the Civil War. And although scholars debate whether one party is guiltier than the other, antidemocratic trends are growing stronger on both sides. If we don’t figure out a way to get this sectarianism under control, I fear for the future of our republic.

Some of those I contacted cite changes in mass media as critical to this increasing sectarianism.

Shanto Iyengar, a political scientist at Stanford and another of the paper’s authors, emailed to say:

I would single out the profound transformations in the American media system over the past 50 years. Basically, we’ve moved from an “information commons” in which Americans of all political stripes and walks of life encountered the same news coverage from well-regarded journalists and news organizations to a more fragmented, high choice environment featuring news providers who no longer subscribe to the norms and standards of fact-based journalism. The increased availability of news with a slant coupled with the strengthened motivation to encounter information that depicts opponents as deplorable has led to a complete breakdown in the consensus over facts.

Iyengar noted that research he and Erik Peterson, a political scientist at Texas A&M University, have conducted shows that:

the partisan divide in factual beliefs is genuine, not merely partisans knowingly giving the incorrect answer to factual questions because they realize that to do so is “toeing the party line.”

In the case of views of Covid, he and Peterson found that even though

beliefs about appropriate health practices can have life or death consequences, misinformation over the pandemic is rampant among Republicans and does not dissipate when we offer financial incentives to answer correctly.

Cynthia Shih-Chia Wang, a professor of management and organization at Northwestern’s Kellogg School of Management and also a co-author of the paper, shares Iyengar’s concern over the role of ideologically driven sources of information.

“Media is a big contributor to political sectarianism,” Wang wrote by email, adding that research she and her colleagues have conducted shows that “consuming ideologically homogeneous media produced greater belief in conspiracy theories endorsed by that media.”

In Wang’s view, Trump’s refusal to acknowledge his election loss is dangerous because of “the number of political elite — the 18 Attorney Generals and 128 members of the House — who are sowing seeds of doubt around the ethicality of the elections,” with the result that

the system is being severely challenged by a president that refuses to concede, by an us-versus-them mentality that contributes to continued congressional gridlock as a pandemic rages, and especially by the doubt cast on the credibility of the American system.

For the moment, Wang wrote,

the system of government seems to be withstanding these unprecedented challenges — the fact that the conservative-leaning Supreme Court dismissed the challenge above should give us some optimism.

Peter Ditto, a professor of psychological science at the University of California-Irvine and another co-author, argued in an email that the most toxic element in contemporary politics

is moralization. Our political culture has devolved into what both sides see as an existential battle between good (us) versus evil (them), and in that environment almost any lie can be believed, almost any transgression excused, as long as it helps your side.

Politics, Ditto continued,

has metastasized into something akin to a religious battle — a war between two sects of the American civil religion, each with its own moral vision and each believing it must defend to the death the “true”vision of the founders against heretics seeking to defile it.

The decision to coin the term political sectarianism “was our attempt to capture the moral fervor of our current political climate and the collateral damage it leaves in its wake.”

Diana Mutz, a political scientist at the University of Pennsylvania, wrote that after every election since 1996, she has asked voters in a poll “about why they think the winner won.” She found that in past years, those on the losing side have consistently claimed the winner was illegitimate for a variety of reasons:

He lied to people in his advertising; he had more money to spend because he represented corporate interests; states changed their voting laws and let illegal people vote; the Russians intervened; they suppressed turnout; the press was biased against him; He was wrongly blamed for [insert here]; some people voted twice; etc.”

“What’s new this year,” Mutz continued “is taking these sour grapes feelings to court.”

Steven Pinker, a professor of psychology at Harvard, provided a complex answer to my inquiries.

“Humans can believe things for two reasons: because they have grounds for thinking they’re true, or to affirm a myth that unites and emboldens the tribe,” Pinker wrote.

Any fair-weather friend can say that rocks fall down, but only a blood brother would be willing to say that rocks fall up. But usually, reality imposes limits on how far we can push our myths. What’s extraordinary about the present moment is how far most Republicans have gone in endorsing beliefs that are disconnected from reality and serve only to bind the sect and excommunicate the unfaithful.

The key but unanswerable question, Pinker continued,

is how strongly reality will push back once Trump’s power and pulpit are diminished. There undoubtedly will be Lost Cause warriors and post-1945-Japan-style cave fighters, and it would be nice to think they will eventually be marginalized by their own preposterousness. But myths can persist within a closed network when belief in them is enforced by punishment, so a denialist G.O.P. faction could survive for a while.

Trump is doing everything he can to perpetuate the myth and has repeatedly demonstrated his ability to avoid marginalization. Goldstone and Turchin argue that Trump is a symptom not a cause of the breakdown of the system. One question that will be answered over time is whether Trump will continue to be uniquely gifted in putting a match to the gasoline. Or has the political, cultural and economic mix become so combustible that any spark can set it off regardless of which party or person is in office?

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