In 1931, Philip Guston and his friend Reuben Kadish painted a protest image and took it to a rally. The rally, in Los Angeles, was in the same vein as the recent Black Lives Matter protests sparked by the killings of George Floyd, Breonna Taylor and Ahmaud Arbery. It was a fundraiser in support of the “Scottsboro Boys,” nine African American teenagers attacked by a lynch mob in Alabama after being falsely accused of raping two White women.

Guston, who is regarded as one of the most influential artists of the past 100 years, was only 18 at the time and was already a serious mural painter. Alive to injustice, he worried — like so many young people today — about a wider descent into chaos and violence.

Preparing for the protest, Guston didn’t just scrawl a slogan on a white banner. He painted a portable fresco, showing a Klansman whipping a Black boy roped to a stake — a reference to the Scottsboro Boys.

Guston had recently joined a John Reed Club (motto: “Art is a weapon in the class struggle”), and after the rally, he stored the panels there. When, later, a Los Angeles police “Red Squad” raided the club, they found the frescos and destroyed them, firing bullets into the Black figures’ eyes and genitals.

This was Guston’s first serious taste of the abuse of state power. And it lodged.

Guston drew on this experience almost 40 years later when he decided to draw a sequence of political cartoons centered on Richard Nixon and his Watergate co-conspirators — Vice President Spiro Agnew, Attorney General John Mitchell and national security adviser Henry Kissinger.

Guston’s Nixon is a Robert Crumb-like figure with a phallic nose (it grows with “Tricky Dick’s” every lie) and jowls puffed out to resemble a bewhiskered scrotum. Agnew appears as a Klansman’s hood with slits for eyes and pins in the back of his neck. Mitchell is represented sometimes as a blob resembling male genitals, sometimes as a Klan hood smoking a pipe. And Kissinger is just a pair of black-rimmed glasses.

Guston drew the cartoons, which were not published during his lifetime, in two spiral-bound sketchbooks in July and August of 1971. The National Gallery of Art has just published them in “Poor Richard,” a softcover book designed like a graphic novel. And next summer, they will go on display there in the first Guston retrospective in 15 years. (The show had been scheduled for this summer, but was put off because of the pandemic.)

Nixon critics tend to associate his name not just with lying and abuse of power, but also with maudlin sentimentalism and elaborate excuse-making. A half-century later, as we approach the end of the first term of a president who, for many people, has taken these same characteristics to a new and rarefied level, Guston’s Nixon drawings look freshly relevant. The connection has only strengthened since President Trump commuted the sentence of his close confidant Roger Stone, a felon with his own Nixon cartoon branded on his back.

In 1971, Guston was no longer painting murals or attending Marxist clubs or even protests. In fact, he had spent most of the 1960s as an abstract painter (motto: “Nothing to see here!”). His considerable prestige derived from paintings tuned to the key of Claude Monet’s Giverny paintings. They were dubbed “abstract impressionism.” In hindsight, they’re repetitive and dull. But at the time, the cognoscenti oohed and aahed about their diaphanous moods and painterly refinement.

Guston himself was neither refined nor elegant. He was voluble. He nursed grievances. He smoked three packets of Camels a day. One of his friends, the poet William Corbett, described him as a “delicate sort of buffalo.” Another, the composer Morton Feldman, called him as an “arch crank.” He was the polar opposite of Nixon. And yet, disconcertingly, there were real affinities.

Guston was born in Montreal in 1913, the same year as Nixon. His Jewish Ukrainian parents, fleeing persecution, had moved from Odessa to Canada, and later to Los Angeles. He and Nixon grew up in nearby neighborhoods.

When Guston was 10, his father hanged himself and it was Guston who discovered the body.

Over the following years, he took to art. He did a correspondence course in cartooning. But he was also a voracious reader, with a special affinity for poetry. And, like Nixon, he adored the movies.

As the ’60s drew to their violent close, Guston grew bored by abstract art. “I got sick of all that purity!” he famously said. “Wanted to tell stories. I felt like a movie director, like opening a Pandora’s box and all these images came out.”

When Guston embarked on his Nixon cartoons, he had just moved from New York City to Woodstock, N.Y., where a friend introduced him to a neighbor, the writer Philip Roth.

Roth was also new to the area. He had just published “Portnoy’s Complaint,” his notorious novel laced with detailed descriptions of masturbation and hilarious, unholy takes on Jewish identity. The uproar in New York’s Jewish and intellectual communities was immense. Roth thought it wise to leave town.

Guston, too, was a heretic in flight from the high priests of culture. The previous year, breaking at last with abstraction, he had mounted a show of figurative paintings featuring hooded Klansmen — cartoon versions of the figures in his 1930s murals — zooming around town in open-top cars, pointing stubby fingers and frantically smoking. These strange, clunky pictures, in a palette dominated by cadmium red, also included bare lightbulbs, the soles of shoes, buildings and bricks.

Guston’s fellow artists were confounded. They felt betrayed. The critics, too, were harsh. In one indelible review, the conservative critic Hilton Kramer lamented the “spectacle of mandarin sensibilities masquerading as unlettered but lyrical stumblebums.”

Guston, like Roth, took off. He flew with his wife, Musa, to Italy. He received from his gallery a package containing all the reviews of his show while in Venice, and threw it in a canal.

Six months later, in Woodstock, Guston spent long nights talking with Roth. Both men shared a love, Roth wrote, for what Guston “called ‘crapola,’ starting with billboards, garages, diners, burger joints, junk shops, auto body shops . . . and extending from the flat-footed straight talk of the Catskill citizenry to the Uriah Heepisms of our perspiring president.”

They worried about the country’s predicament: assassinated leaders, civil rights showdowns, police crackdowns, Vietnam. And they loathed Nixon’s self-serving sentimentalism. Watergate was still on the horizon. Nixon was making overtures to Communist China. He had just announced plans to travel there, having already sent Kissinger on a scouting trip.

Roth’s creative response to all this was “Our Gang,” his follow-up to “Portnoy’s Complaint.” The opening chapter, a satirical conversation between Nixon and an obsequious interviewer, was published in a May 1971 issue of the New York Review of Books, just as Guston returned from Italy. It was the catalyst that got Guston going on his Nixon cartoons.

Guston did his research. He read Nixon’s “Six Crises” and a biography of the president by Garry Wills. On the other side of a creative gush that produced 164 drawings, he prepared a sequence of 73, which he likened to a home movie or an animated cartoon.

The first half shows scenes from Nixon’s early life: as an insomniac boy dreaming of a glorious future, a college footballer, a senator in a patchwork suit with a checkered dog attached to his sleeve (a reference to Nixon’s “Checkers Speech”). The second half burrows into Nixon’s China plans, with surreal results. Kissinger, for instance, flies to China in a small plane and is shot back to Capitol Hill by a Chinese canon.

Guston was, in fact, influenced by surrealism, and by the proto-surrealist Giorgio de Chirico in particular. (The boat and the steam train outside young Nixon’s bedroom window in the first two drawings allude to de Chirico’s “The Enigma of Arrival” and “Gare Montparnasse (The Melancholy of Departure).”)

He loved Piero della Francesca, too, and saw the Renaissance artist’s multipanel frescos, in Arezzo as early forms of comic-like storytelling. Looking at other drawings in “Poor Richard,” it appears he had also devoured the graphic creations of Crumb and Saul Steinberg.

One of Guston’s friends, the Boston-based poet William Corbett, urged Guston to publish his Nixon cartoons and, having encouraged him to prepare a dummy, connected him with an agent. The dummy “went to every good publisher,” Guston told an audience of students in 1973, “but all the lawyers were afraid to do it.”

Corbett and others, however, believed that Guston himself was the obstacle. He was of two minds. He wanted to be politically engaged — as he had been in his youth — but he didn’t want to be perceived as yet another crazed lefty driven to extremes by Nixon. Nor did he want the reception of his recent paintings, which had so baffled the art establishment, to be muddied by the appearance of political cartoons.

The brilliant graphic novelist Chris Ware understood Guston’s reservations: “The last thing I would want as my artistic legacy would be a stack of Mitt Romney, George Bush, and Strom Thurmond cartoons,” he wrote in a piece about Guston’s Nixon drawings in the New York Review of Books. “In the grocery store of art, political cartooning has the shelf life of an avocado.”

Guston must have noticed, concluded Ware, that his images of Nixon and Agnew “simply didn’t have as much staying power as his Platonically powerful paintings of heads, bottles, legs, shoes, and lightbulbs.” He was probably right.

A political cartoon is usually pointing the finger at others. Guston’s great paintings of the ’70s are of a different order. They are about failure, befuddlement and the evil in all of us. They’re also about loneliness, and the endless existential comedy of what the English call simply “carrying on.” They belong in the same category as Samuel Beckett, Italo Svevo and Federico Fellini.

Guston embraced dark political realities as subject matter for serious art, but he refused the moral high ground. He understood, as Corbett wrote in a fine memoir about Guston’s late work, that “the human reality of American corruption and political violence is not simply a matter of us and them.” Displays of outrage, he saw, deflect us from deeper truths.

Still, if we believe that art can be more than one thing, that a repertoire is often better than a singular obsession, and that corrupt leaders should always be pointed out and laughed at, Guston’s overall achievement is not spoiled — it can only be enriched — by acknowledging that he made some of the most brilliant political cartoons of his time.