Peter Saul at the Orange County Museum of Art

Peter Saul is some kind of national treasure. Just what kind of national treasure is hard to say.

Perhaps that’s because his best paintings refuse to be ingratiating, while the tides of popular culture that wash over us like a daily tsunami are all about gaining our favor. He’s a Pop artist, but he doesn’t play by the usual rules.

Saul wields his brush in ways certainly meant to get a viewer to look at his pictures long and hard, using complex color and refined form in sophisticated, eye-grabbing ways. But the contemptible, despicable and even humiliating are what you’re likely to encounter in his imagery. The clanging dissonance between hot form and chilling content can be oddly riveting.

The California-born artist, who turns 74 this month, is the subject of a modest but rewarding 40-year retrospective at the Orange County Museum of Art. One of the most recent paintings, “Stalin in 1943” is representative of his work’s inescapable if peculiar charms. The big, raucous picture is like a lowdown comic on steroids.

Nine feet wide and 6 1/2 feet tall, the rectangular format’s aspect-ratio is roughly the same as TV. Russian strongman Joseph Stalin is dressed as a Soviet general but has a pair of six-guns blazing, like something out of a John Wayne western.

Screaming bullets rip gaping holes in the floating heads of helmeted Nazi soldiers, who are smashed against the right-hand canvas edge, even tearing one or two in half. The Germans return fire, but it’s limp and ineffectual. These goggle-eyed soldiers are goofy sad sacks, like refugees from “Hogan’s Heroes,” while big-shouldered Joe fills more than half the imposing canvas. The implacable superman is a colossus astride a ferocious battle, whose outcome is not in doubt.

Stalin a heroic cowboy? A brutal dictator, responsible for the deaths of millions of his own countrymen during a quarter-century of rule, a good guy? Well, maybe compared with the Nazi nightmare -- but do we have to go there?

Saul does. He paints Stalin as a torso with feet, a caricatured little person, which approaches the Russian’s actual short, Napoleonic physical stature. But the real life the artist seems fixated on portraying, in exquisitely executed acrylic colors highlighted in luminous oil glazes, is one in which good and evil are fictitious absolutes.

Stalin was a hideous creep; Nazis were hideous creeps. In World War II, the fate of Western civilization hinged on a slugfest between hideous creeps. Yes, those competing values of good and evil exist, but only a madman would divide the world into black-and-white camps.

Saul’s painting “Columbus Discovers America” shows the cartoonish explorer -- he looks like Cyril Ritchard as Peter Pan’s prancing Capt. Hook -- as a brutal killer, wielding a crucifix as a machete. But he also portrays Columbus’ indigenous victims as caricatured cannibals, toting platters piled with body parts through the jungle. Nobody gets out of a Saul painting unscathed, never mind beatified.

That’s because there are no saints, just people with myriad human flaws, whether gorgeous or grotesque. Saul is about the only artist I can think of who could paint a portrait of President Bush at Abu Ghraib prison and illuminate rather than simply rebuke (or -- shudder -- extol) the horror.

The painting is a double portrait, with Bush and an Iraqi victim side by side before a wall of green bricks. Within this fortress-like Green Zone, the bust-length Bush portrait is affable: blue suit, red tie, neat coif, cheerful grin.

By contrast the prisoner, who wears an acidic yellow-green shirt, looks like something from Mad magazine or Weird Tales. His face is smashed, scrambled and askew. Buck teeth protrude from multiple orifices, three eyeballs droop and brains ooze from his head, which is pocked with bullet holes. He’s strung up with a winch.

And then, the kicker: Bush has his arm around the comic Iraqi’s shoulder, like he’s a pal, as his index finger reaches up to probe inside the freakish monster’s lip. (The finger is not in his nose, as the otherwise fine exhibition catalog asserts; in fact the lip has an almost Freudian sexual overtone.) This shocking gesture transforms an already strange image into an astounding echo of Jesus and doubting Thomas, the apostle who poked the wound in the risen Christ’s body to convince himself of the miracle’s flesh and blood reality.

That biblical account was rendered by many Old Master artists, most famously CaravaggioOrange County Museum of Art. Saul’s “Bush at Abu Ghraib” is so gorgeously painted that this devastating recollection -- and its implications -- makes you gasp. The decider, an anonymous creature, the battle between good and evil, religious frictions, a subliminal eroticism yoked to violence -- a painting that in lesser hands might be a cheap bit of propaganda or preaching to the choir instead blossoms into a haunted meditation on the depths of human cruelty.

The 32 paintings and 17 works on paper in the OCMA show, assembled by guest curator Dan Cameron, show Saul warming to political subject matter after 1965. Briefly a student at Stanford and the California School of Fine Arts, he graduated from Washington University in St. Louis in 1956, when Abstract Expressionism was the leading avant-garde form. In Missouri, though, the biggest impression was apparently made by the legacy of Jackson Pollock’s teacher, Thomas Hart Benton, with his often jingoistic subject matter, and expatriate German Expressionist Max Beckman, with his suave images of human brutality.

Saul spent most of the next decade in Europe. When he returned to the U.S. it was to Mill Valley, Calif., to be near family. Only recently did he move to Manhattan, after sojourns in upstate New York and, from 1981 to 2000, a fruitful period teaching at the University of Texas, Austin. Saul has not been controversial during his career so much as he’s been slightly off the radar -- not quite a cult figure, but an outlander hero to numerous younger artists who now have bigger reputations than his, including Jim Shaw and especially Mike Kelley.

A turning point came in 1963, with a series of paintings of refrigerators with the door ajar. Several open the show. Andy Warhol had painted the subject in 1960, but Saul’s “Icebox” works don’t look like handmade newspaper advertisements showing foodstuffs lined up neatly on shelves.

There is steak, cake, ham and soda, but also furniture, a cross-eyed Disney duck, cigarettes, money, a toilet seat, genitals and signage -- the accouterments of daily life, put on ice. A gun blasts a yapping pooch in a casual act of sadism toward man’s best friend, while a hand hammers a nail into the palm of another hand in a disturbing act of self-crucifixion.

Stylistically, these paintings are more like Jean Dubuffet and street graffiti than slick Pop Art. (They anticipate Philip Guston.) Thick oil paint, dry and heavy, gets traded in for synthetic polymers and acrylic in the 1970s, with oil reserved for thinned, light-loving glazes. Saul’s career could be followed as a steadily increasing formal mastery, bringing painting’s arsenal of effects to bear on politically volatile subjects. The Vietnam War, capital punishment, religious hatreds, racial hostility, murder -- he paints them all with skillful ardor.

In 1976 he painted an homage to his generation’s most technically gifted painter, “De Kooning’s ‘Woman With Bicycle,’ ” and it’s the most conventionally gorgeous picture in the show. It’s also very different from its source. Much larger than the 1952-53 original, it uses the De Kooning as an armature but sets aside his much-loved whiplash line, labored surface and ferocious color. In their places are crisp, sleek shapes; a carefully organized, almost Cubist spatial composition; and a palette of lime, purple, watermelon and screaming yellow. Saul’s painting is like a tour de force of DayGlo Jell-O.

Missing from the show are any of the 1970s paintings of art world celebrities and politicians. But this compact survey is otherwise quite good at articulating Saul’s main themes and artistic evolution. The best paintings are genuinely scary, which in a brawny American society compulsively driven by fear typically means this art would be shunned (or worse). Being a national treasure just isn’t for the faint of heart.

christopher.knight@latimes .com