At best, "Rambo: First Blood Part II" is a crudely effective right-wing rabble-rouser, the artistic equivalent of carpet bombing -- you don't know whether to cheer or run for cover. At worst, it's a tribute to Sylvester Stallone, by Sylvester Stallone, starring Sylvester Stallone. "Who's the fairest of them all?" says Sly into the Hollywood mirror. Or rather, "Hoozafairesuvvamaw?"

"Rambo" is the sequel to "First Blood," Stallone's first (and only) big hit since the "Rocky" movies. Viet vet John Rambo (Stallone), having shot up a small town in the first film, is splitting rocks in a hard-labor penitentiary when his Special Forces mentor, Col. Trautman (Richard Crenna), arrives with a proposition: If Rambo will return to find MIAs still held by the Vietnamese, he may win a presidential pardon. "Do we get to win this time, sir?" Rambo asks.

According to the credits, the director of "Rambo" is George P. Cosmatos, but its true auteur is Stallone, a notoriously aggressive rewriter and redirector who tailors his movies to his own preening presence. At this point, it's almost useless to complain about Stallone; barring a commando raid by the nine Muses, we're stuck with him, his lasagna lips, his droopy blankness, his anatomical hypertrophy. Again and again, we watch his oiled muscles flexing and bulging while catches fasten, guns clatter or a huge bowie knife kachunks into its scabbard in Dolby stereo. His torturers strap him to an electrified bed frame just so we can watch his splendid abdominals undulating like a harem dancer's -- less machismo than Me-chismo.

Stallone underplays emphatically, his face sealed in amber, his lines pared to monosyllabic croaks; he means to tell us that still waters run deep, but it seems more like the dead man's float. In all his performances, this impassivity finally fragments into a monologue of screaming, potato-mouthed histrionics, and "Rambo" is no different. "Don't hate your country for it," Trautman tells Rambo, after he's been backstabbed by Washington for the umpteenth time. And the marbles in Stallone's mouth are off and clattering. "Hate? I'd die for it! For our country to love us as much as we love it -- that's what I want!"

Crenna reprises his role from "First Blood" -- he even has much the same dialogue, all that stuff about how Rambo is a "pure fighting machine." He seems to have slimmed down through his association with Stallone, but the movie doesn't do much else for him -- like all the elaborate military hardware, he's just a prop to the star's vanity. He's a resourceful, witty actor, sly in the ways he undercuts his characters, so he's lost in a movie this fatuously earnest, a role so unfailingly wooden.

While the moralisms of the dialogue, the self-righteous tirades about the treatment of Vietnam veterans, sound like Stallone, the line of the story belongs to Stallone's cowriter, James Cameron. After "The Terminator" (which he also cowrote), Cameron is developing into a canny screen writer with an affection for excess, a solid grounding in the stylized movies of the past, and no scruples whatsoever. The vets-fight-the-war-again "Rambo" predecessors ("Uncommon Valor" and "Missing in Action") had simple, linear plots -- they were engines to set up the climactic battle at the end. Cameron layers the story with occasions for action, repeated captures and escapes and enough explosions to make Mr. T seem like Mister Rogers.

And he gives "Rambo" no fewer than three sets of villains. The mission is run by Murdock (Charles Napier), a sleazy intelligence operative dependent on computers rather than his own guile, who cares more about geopolitics than the lives of the POWs (the operation, Trautman tells him, is "a lie, just like the whole damn war"). Once inside the camp, Rambo is tortured by both Vietnamese and Russians (led by the sinister Steven Berkoff); in Cameron's imagination, they're transformed to the Japanese and Germans of '40s propaganda films. The Vietnamese even wear those thick glasses and boxy camp hats the movie Japanese wore; and Berkoff, fastidiously sneering through his interrogation, might as well be George Sanders in "Man Hunt."

But there's a fine line between having fun with old movie conventions and becoming a hack yourself, and Cameron crosses it here. "Rambo" is standard audience manipulation all right, but of a particularly disturbing kind.

What "Rambo" resembles most of all is not the American propaganda movies of World War II, but the Nazi and proto-Nazi cinema of the '20s and '30s. It has all the elements: the Aryan hero; the warrior concubine -- Rambo's Vietnamese guide, played by Julia Nickson; the inspirational shots of tall mountains; the emphasis on primal virtues; the mute, expressionless killer; the ideology of an Army undercut by the government back home.

Here's a movie that wears its brown shirt on its sleeve. Franco Columbu is credited in "Rambo" as "Body Building Coach." Congratulations, Franco -- Sly's body looks fine. Now can't you come up with a workout for his soul?

Rambo, opening today at area theaters, is rated R and contains graphic violence and some profanity.