Here’s the good news: The chaos and upheaval we see all around us have historical precedents and yet America survived. The bad news: Everything likely will get worse before it gets better again.

That’s my chief takeaway from “Shattered Consensus,” a meticulously argued analysis of the growing disorder. Author James Piereson persuasively makes the case there is an inevitable “revolution” coming because our politics, culture, education, economics and even philanthropy are so polarized that the country can no longer resolve its differences.

To my knowledge, no current book makes more sense about the great unraveling we see in each day’s headlines. Piereson captures and explains the alienation arising from the sense that something important in American life is ending, but that nothing better has emerged to replace it.

The impact is not restricted by our borders. Growing global conflict is related to America’s failure to agree on how we should govern ourselves and relate to the world.

Piereson describes the endgame this way: “The problems will mount to a point of crisis where either they will be addressed through a ‘fourth revolution’ or the polity will begin to disintegrate for lack of fundamental agreement.”

He identifies two previous eras where a general consensus prevailed, and collapsed. Each lasted about as long as an individual’s lifetime, was dominated by a single political party and ended dramatically.

First came the era that stretched from 1800 until slavery and sectionalism led to the Civil War. The second consensus, which he calls the capitalist-industrial era, lasted from the end of the Civil War until the Great Depression.

It is the third consensus, which grew out of the Depression and World War II, which is now shattering. Because the nation is unable to solve economic stagnation, political dysfunction and the resulting public discontent, Piereson thinks the consensus “cannot be resurrected.”

That’s not to say he’s pessimistic — he thinks a new era could usher in dynamic growth, as happened after the previous eras finally reached general agreement on national norms. But first we must weather a crisis that may involve an economic and stock-market collapse, a terror attack, or simply a prolonged and bitter stalemate.

The book, like its author, is conservative but not doctrinaire. Piereson, president of the William E. Simon Foundation and a senior fellow at the Manhattan Institute, uses a scholarly Big Idea template to dissect a variety of examples that at first glance seem to be digressions. Not so — he methodically accumulates evidence for relevant and compelling conclusions.

A chapter on the impact of the JFK assassination is so riveting that I ­insisted on reading portions aloud to my family. How, Piereson wonders, was it possible that Fidel Castro and Che Guevara became heroes to the American left when it was a committed communist who killed the left’s beloved Kennedy?

Piereson also deftly demolishes the myth of Camelot by recounting how a grieving first lady created the legend on a single weekend after the president’s funeral. Jacqueline Kennedy invited famed writer Theodore White to the family compound on Cape Cod so he could interview her for a Life magazine issue devoted to JFK.

There she told White that she and the president went to bed listening to the soundtrack of the then-popular Broadway show “Camelot,” which was based on a novel. She insisted that JFK loved the music and the story because he, too, was a courageous idealist like the fabled King ­Arthur depicted in the show. “There will be great presidents again, but there will never be another Camelot,” Jackie told White.

White and his editors resisted the grandiose and sentimental story line, but finally relented to the grieving widow. White later expressed regret for helping to create the Camelot myth.

Other sections trace the changes of liberal and conservative orthodoxy and the rise and decline of American universities.

Piereson also considers possible ­elements of the next national consensus, including a renewed focus on growth instead of redistribution and a bid to depoliticize government.

But he is ultimately uncertain what will come next because we are far from reaching a consensus on almost anything. There are so many fault lines that the nation seems consumed by a conflict of all against all.

That doesn’t make for a happy ending, but it is an honest one, and that’s another virtue of this terrific book.

Meerkats, apes, llamas? Oh, my!

The best first paragraph of the week comes from The Associated Press:

LONDON — A former meerkat expert at London Zoo has been ordered to pay compensation to a monkey handler she attacked with a wine glass in a love spat over a llama-keeper.

Gov’s latest de Blasio diss

The news that Gov. Andrew Cuomo will attend a fundraiser for Rep. Hakeem Jeffries ups the ante in his feud with Mayor Bill de Blasio. The fundraiser is for Jeffries’ congressional re-election, but because he’s often cited as a potential challenger to The Putz, Cuomo’s role shows he isn’t interested in making peace with de Blasio. Don’t be surprised if the governor pushes Jeffries to enter the 2017 mayoral race.

NYC’s absent minded parents

City Hall’s massive data dump of health conditions in New York’s neighborhoods uses so many measurements that the only guarantee is a fog of statistics.

The community profiles purport to measure how many times a week people in Bed-Stuy eat fruits and vegetables, how many times residents in Midtown exercise and how many tobacco retailers there are in Bayside. They count air-pollution particles, psychiatric hospitalizations and poverty rates.

Still, one number cited in The Post for a Brooklyn community stands out. In Brownsville, schools report that 40 percent of local elementary students are chronically absent, meaning they miss at least 20 days a year. The citywide average is 20 percent, though it varies greatly based on race and ethnicity. In the largely white Financial District, only 4 percent of students are chronically absent.

Attendance is one of the best predictors of educational success. Students who aren’t in school can’t learn, and are more likely to drop out, commit crimes and go to jail. They’re also more likely to have children out of wedlock who will repeat the life pattern.

We’ve known this for decades, just as we know the decision by parents to let their kids skip school is not caused by poverty, racism or inequality. The students are too young to make such important decisions, so it’s adults who are making the free choice to deny their children an education.

That’s child abuse by neglect. Let’s see City Hall measure that.