Films that help us remember how recent history happened

Historical themes are vevy much with us in today's movies. And it's not entirely a frivolous interest based on idle curiosity or perverse nostclgia. There seems to be a serious concern that past events must be remembered if they are to be understood and learned from.

Thus the epic ''Reds,'' an intermittently intelligent film by Warren Beatty, is leading the Academy Awards race with 12 nominations. ''Ragtime'' also probes 20th-century history, though its political overtones are less forceful than those of E.L. Doctorow's original novel. ''Missing,'' with its superb performances from Jack Lemmon and others, deals with more recent events as it follows an American businessman's hunt for his vanished son after a Latin American coup.

And other countries have contributed to the recent spate. ''The Boat Is Full, '' a Swiss contender for the best-foreign-film Oscar, deals with the tragic problem of Nazi refugees during World War II. ''David,'' from West Germany, chronicles the experiences of a young Jewish boy during Hitler's rise to power. The rough-and-tumble actionof ''Das Boot'' gives an antiwar slant to the savage submarine warfare of World War II, as seen through German eyes, and even ''Chariots of Fire'' gives a bit of insight into the workings of the British mind in the first quarter of this century.

Now the trend toward historical study continues in two new documentaries about the period of World War II and its aftermath. One announces its tragic subject right in the title: ''Genocide,'' a plain-speaking look at the origins and effects of Nazi atrocities. Nominated for the ''best documentary'' Oscar, it was directed by Arnold Schwartzman for the Simon Wiesenthal Center, a Holocaust museum and study center at Yeshiva University of Los Angeles. After a limited engagement beginning Sunday in New York, it will embark on a tour of the United States.

''Genocide'' is no grainy collection of familiar atrocity footage. If anything, it is overproduced, with flashy editing and camera gimmicks (plus a honey-throated narration by Orson Welles and Elizabeth Taylor) distracting attention from the grim business at hand. But such frippery is easily overlooked as the film gathers momentum. What makes ''Genocide'' a valuable addition to the cinematic record of Nazism is its thoroughness, its willingness to start at the beginning and document the gradual growth as well as the horrendous results of the bloated bigotry that led to Hitler's extermination campaigns.

The film begins by briefly recounting the long history of anti-Semitism. Hitler's ideology of hate is thus seen not as a unique phenomenon, but a new manifestation of an old and perennially pernicious idea. Despite the film's Jewish credentials, it is also careful to remind us, more than once, that not only Jews were on Hitler's death lists. Others perished too, from homosexuals to the handicapped, and their fates are duly chronicled. In addition, Hitler's enormous persuasiveness over his nation and his people is outlined, evoking the mentality of the ''good German'' -- a crucial cog in the Nazi phenomenon -- fairly and forcefully.

Unlike some ''educational'' movies on Nazism and related subjects, ''Genocide'' has an immediacy that is equal to its scholarly care and historical concern. Above all, this is a hugely sad film, full of wonder that such things could have happened and determined to remind us in hopes of preventing them from happening again. So few years have passed since Hitler's heyday that it seems remarkable the Nazi years are thought by some to be in danger of fading from public memory. The starkly titled ''Genocide'' is an artfu attempt to forestall such forgetting, now or ever. Attention must be paid.

Moving to the period after World War II, the enterprising Film Forum in New York is introducing a fascinating new movie called ''The Atomic Cafe'' -- a ''compilation film'' composed of documentary and propaganda footage, all dealing with the subject of nuclear power during the cold war. An alternately chilling, harrowing, and hilarious picture, it continues at the Film Forum through Marcx 30 and has its West Coast premiere March 27 at the Filmex festival in Los Angeles. It deserves to be seen everywhere, and if American movie distributors are on their toes, it will be.

To quote a statement by Karen Cooper, who runs the Film Forum, ''much of what we know, think, feel, desire, and fear'' is defined by TV and movie images, newspaper headlines, and other not-so-hidden persuaders, all ''written and photographed, selected and shaped, reworked and edited for our consumption.'' The makers of ''The Atomic Cafe'' have put together 88 minutes of government, military, and educational materials -- first seen in movie theaters, classrooms, training sessions, and early TV sets -- designed to ''sell'' the atomic bomb to the American people in the 1940s and '50s.

As an exercise in nostalgia, ''The Atomic Cafe'' works wonderfully well, complete with ''I Like Ike'' sunglasses and Bill Haley rock 'n' roll. But the film's real meaning lies on deeper and far more serious levels. Using primary sources from the early atomic era, it examines the roots of American thought regarding the ''A-bomb'' and the ''H-bomb,'' and demonstrates that -- a mere 30 years ago -- these apocalyptic weapons were being eased into the popular consciousness as handy tools, friendly protectors, ''gifts from God,'' and at worst, remote threats that didn't deserve much consideration from just plain folks.

Looking back on the first days of the atomic age, it's downright frightening to contemplate nuclear bombs in the hands of people capable of the racism that oozes from a military film about the ''happy, simple'' people of Bikini atoll. It becomes hard to imagine how we ever survived the pointedly stupid logic that told TV viewers not to spend 85 percent of their time worrying about a weapon that poses a mere 15 percent chance of killing them; or the ostrich mentality that led to cheerful advertisements for backyard fallout shelters (''stay inside for at least an hour after the attack'') and lead playsuits for children.

We did survive those years, but what mental seeds were planted by such pernicious propaganda? How much popular blindness to the threat of nuclear war stems from American smugness over Hiroshima and Nagasaki, self-congratulation over receiving such powerful ''gifts from God,'' and artificially implanted trust in generals and politicians who must ''know more then ordinary people'' because they say they do?

Graphically and potently, ''The Atomic Cafe'' thrusts these questions before our eyes. It is not entirely ''objective'' - this material too has been selectively edited - but its methods are generally as responsible as its message. High praise goes to filmmakers Kevin Rafferty, Jayne Loader, and Pierce Rafferty, who painstakingly plowed through various archives in search of the documents they bring to our attention so effectively, without benefit of narration. ''The Atomic Cafe'' should be seen by everyone who cares about atomic power, the threat of nuclear war, the roots of American culture, or the pervasive effects of the images and ideas that blitz our minds every day through the mass media. In its own modest way, it's an explosive movie.