(Knopf)

Jane Smiley’s Last Hundred Years trilogy narrates the chronological history of one Iowa farm family, the Langdons, over five generations. In the process, it also tells the story of white middle America: how most Americans abandoned the farm for college, war and city life; how a few stayed behind, struggling to hold on to the land; how each ensuing generation accumulated learning, sophistication, power and wealth; and, most crucially for this last volume, how they witness the imminent destruction of the planet (while still enjoying home-cooked meals).

You can’t accuse Smiley of lacking ambition when she sits down to write a novel or three.

Like “Some Luck” and “Early Warning,” the trilogy’s first two volumes, “Golden Age” devotes one chapter to every year (1987 to 2019), and it expects a reader to keep up with scores of characters. The first 30 pages may begin with a head-scratching sorting out of the cousins until characters come back into focus. Fictional lives dissolve into the fantastical details of our real history, but the future reads as utterly believable realism. The march of time is sometimes a slog — we hit the doldrums in the early 21st century — and the prose is workaday, but the humor is as dry as in the previous novels, and Smiley has sharpened her satiric blade. She’s out for blood this time.

She also continues to strike a fine balance between the history of an era’s “great ideas” and the history of its everyday life. The Langdons lose a family member to 9/11, and some among the clan go off to do battle in Iraq and Afghanistan, but the particulars of personal suffering do not overwhelm the intellectual arguments (and vice versa). If crucial areas of the country’s last 100 years get glossed over — racism and immigration are acknowledged, but not explored in depth — it’s a small miracle how much ground Smiley covers and how much she knows: about biochemistry, horses and genetics, but also medieval literature, financial instruments and especially politics.

Novelist Jane Smiley (Derek Shapton)

Indeed, the family’s involvement in politics is the central concern of “Golden Age.” Smiley is fascinated by how individuals and institutions wield power. Michael, the bullying twin to Richie Langdon, generates vast wealth and uses his ruthless charm to intimidate his brother, a congressman, and steal from his mother. His Lady Macbeth wife, Loretta, befriends an authoritarian Catholic priest to help keep Michael in line, and later arranges an abortion despite her avowed opposition. The stench of hypocrisy and corruption permeates these pages, and the foul odor wafts through the halls of Congress, where Rep. Richie Langdon of Brooklyn is a feckless, weirdly likable, moral coward.

Smiley’s brief acknowledgments include a note of thanks to the “members of the U.S. Congress for being so easy to satirize.” Plenty of real politicians appear. Rep. Jerrold Nadler (D-N.Y.) on the long-suffering left, and Vice President Dick Cheney of the conniving right get lots of play, but Smiley also tells all about think tanks, congressional schedulers and cousins who drop a line to their personal congressmen. The Langdons choose their political sides with free will, but there’s a decided authorial tilt toward the progressive, and more than a hint that this Romulus and Remus — Michael and Richie — have founded a legacy bound to destroy itself.

What tempers the satire is the meticulous attention Smiley pays to the “random act of human breeding.” When Felicity Langdon looks in the mirror, she sees both sides of her family: “Five feet, ten inches, 139 pounds, size 9B shoe, thick, dark Guthrie hair, and horn-rimmed glasses. She had an alto voice, a strong jaw, a triangular Langdon nose, blue Langdon eyes, 36C breasts with nice cleavage, and a good waist. She was not beautiful or blonde — an advantage.” She is built to take on the problems of her brother Guthrie — to help him overcome PTSD, acquired in Iraq, and lift him from the torpor of his meth-soaked environment back in Iowa.

We have seen Felicity’s precision and determination before, in her father, Jesse, and her grandfather Joe, the farming Langdons who have remained faithful to the land and have been seduced by innovations that will eventually undermine Jesse’s efforts to keep his farm. And we have seen variations on Guthrie’s trauma before, too, but we cannot predict where his struggle will take him, and what that will say about our country’s future.

With the large cast of characters she is wrangling, Smiley often has to settle for more breadth than depth, and it’s one of the small frustrations of this novel that the wholly intentional focus on the family’s catalogue of accumulated stuff — clothes and kitchen gear and cars and farm equipment — certainly mirrors our consumerist culture but also makes many of the Langdons seem like our own distant relatives, dimly defined by their possessions.

As the novel hurtles toward the future, though, it picks up narrative, philosophical and political steam. The motifs of nature that Smiley has so carefully constructed are in clear danger from capitalism run amok. “Golden Age” traces a direct line from Michael’s thievery and high-finance sleights-of-hand to industrial farming and ecological disaster. Although Claire Langdon has the cheesy perception that “all golden ages were discovered within,” the ending looks grim. Still, there are plenty more mad-as-hell Langdons on the scene, and therein Smiley plants the seeds of possibility for America.

Valerie Sayers, a professor of English at the University of Notre Dame, is the author of six novels.

GOLDEN AGE

By Jane Smiley

Knopf. 443 pp. $26.95