If a conservative is someone who wants to see the Sandinistas overthrown and a liberal is someone who doesn't but believes they are a rotten bunch, then a leftist is someone who still sings the Sandinista song. What must have been the bulk of Washington's left gathered in a Georgetown theater last week for the screening of a film about the Nicaraguan contras. It was the Washington premiere of "Latino," Haskell Wexler's fictional account of the civil war in Nicaragua. A good time was had by most.

To call the film a cartoon is to be generous. After "Latino," "Rambo" takes on the subtlety and depth of "War and Peace." I'll give you the characters and spare you the plot.

The Sandinistas are all happy, singing, guitar-playasants, gun in one hand, hoe in the other. The contras: a scruffy, bearded lot, who rape and pillage before lunch just to get the day going. Violence for them is a kind of brisk pick-me-up.

And two American Green Berets run the raids into Nicaragua. One is just a cold-blooded Nazi. The other is the conflicted "Latino" of the title. After two hours of bedding one Sandinista and killing bunches of others, he achieves "enlightenment," as the press package helpfully explains. He, too, will soon learn to love the revolution.

The audience, an invited group somewhat to the left of Daniel Ortega, appeared appreciative but unappeased. After the film, during the question period with Wexler, one guest complained that the torture scene -- Sandinista boy bound to an electrified bed frame and repeatedly shocked -- was too tame. Why are you pulling your punches, he asked?

Wexler says in an interview that for this scene he benefited from the "dramatic coaching" of Sandinista commandante Tomas Borge, who happened on the set. Borge, once tortured by Somoza's forces, is now interior minister in charge of the new Nicaragua's secret police. He knows his subject well.

During the question period, Wexler was accompanied by two props. One was an academic, William LeoGrande of the left professoriate, there to supply the facts to support Wexler's prejudices. The other was actress Daryl Hannah ("Splash"). She is not in this movie. Wexler carries her around, I presume, to attract a crowd. Her connection with Wexler is family (he is her uncle) and politics (they are both Sandinista believers). Painfully shy, she made a nervous, two-line declaration of political faith at the beginning of the question period, then sat down.

Judged purely as propaganda, the film is an utter failure. From such an audience, Wexler was able to elicit just one laugh and two rounds of applause. The laugh came when a kidnapped Sandinista is made to say "God Bless America," and inadvertently leaves out the "b": "God-less America." Pause, then laughter and applause. The other occurred when that same Sandinista, who had pretended to collaborate with the contras, finally turns his gun on the American "Latino" and explains, "----you, Jack." Applause.

It is not that I have an aversion to propaganda. I like it when it is well done. Costa-Gavras, the film maker most famous for "Z" and "Missing," is no less left than Wexler, but he makes movies. He specializes in political dramas set in brutal pro-American regimes (Greece under the generals, Chile, Uruguay) where the United States is cast as the senior, sometimes invisible, partner in evil. His technique is so dazzling, his narrative so riveting, that when you leave the theater you may not accept his views, but you have acquired a measure of respect for them.

Americans are just not very good at this sort of thing. About the only propaganda movie I can think of more risible than "Latino" is also American- made. "Mission to Moscow," made at the height of World War II Russophilia, can now be enjoyed only for its sheer, outrageous heavy-handedness. Based on the memoirs of Joseph Davies, the U.S. ambassador to the Soviet Union, it is, to be brief, a paean to Stalinism and the kindly "Uncle Joe" ("a great builder for the benefit of mankind").

Most amusing is not the socialist realism (at the end, proletarians march to heroic music up to a city in the sky), but the adoption of Stalin's parochial obsession with Trotsky, whose "saboteurs," it seems, are responsible for the rare blemishes on Soviet life. The film's apologetics for such inconveniences as the Hitler- Stalin pact and the purges of the '30s have, well, Stalinist subtlety. The American ambassador, sitting in the gallery at the notorious Moscow show trials, assures the viewer that though the confessions appear rehearsed and false (at the time, a common charge, and absolutely true), in fact they are not: just Trotskyites in league with Hitler.

"Latino" -- Mission to Managua -- continues the grand tradition of the comically inept American propaganda film. Yet propaganda this bad has its uses. It reminds us that there are societies where this kind of stuff is to be found on the air and in the air everywhere. Places where the slogan of the interior ministry, home of the secret police, is "Sentinel of the People's Happiness." Places like Managua, where that joyous message graces the headquarters of torture consultant and Interior Minister Tomas Borge.