The other night I saw a movie called "The Atomic Cafe." It is a documentary in which old Cold War-era newsreels and propaganda films are used to depict an America so caught up in rabid anticommunism that it uncritically embraced the atomic bomb. I had an interesting time. The audience watched the film and I watched the audience--and wondered about the antinuclear movement.

The film showed the anticommunism hysteria in America, the advent and then deepening of the Cold War, and the concurrent belief that all that stood between us and the Red hordes--the qualms of liberals, pinkos and commies notwithstanding--was the bomb. To a whole generation of Americans it was seen as the great equalizer, and if the Russians threw it back at us, no problem. With a proper shelter, the bomb could be less menacing than the twister that sent Dorothy off to the land of Oz.

The picture you get of America is of a country gone bonkers. And indeed that was somewhat the case. The anticommunism and general intolerance of the period was ugly. (So, for that matter, was the clothing.) But all of it is either shown without context, or the context is parodied. You would think from watching this film that Americans had little reason to fear communism or, in particular, the Soviet Union--that the Soviets had not, since the war, colonized Eastern Europe and played a hand in the Korean War.

But of course, history tells a different story. It tells a tale not only of postwar Soviet expansionism, but of a regime so ruthless that since 1917 it has killed or contributed to the death of tens of millions of its own people. The actual number is open to debate and will probably never be known, but suffice it to say that even the lowest figures would make Joseph Stalin history's foremost mass murderer.

Stalin is dead, of course, and new and more moderate men rule in his place, but the Soviet Union of today, no matter how remarkable its improvement, is a long way from being a benevolent regime--no pal of peace. Yet the Soviet Union is not being discussed in those terms. As in the film "The Atomic Cafe," the growing antinuclear movement here seems to be operating without any context--as if the problem were only in Washington and not also in Moscow.

It's wrong to characterize any movement as all one thing, and the antinuclear movement is no exception. It is made up of many parts, some of them thoughtful, reasonable and downright hard-nosed. But some elements of the movement are wishful, romantic, even silly. It seems to have a kind of flower-child mentality, as if through some combination of marches, folk songs and newspaper ads the world's nuclear stockpile simply will go away--ours first. But you cannot demand an end to the nuclear standoff. It is like demanding a 26-hour day or thinking that just because something is right and makes sense, it will come to pass. If that were the case, no one would smoke.

No matter. Hunks of the antinuclear movement do not want to be bothered with details, such as what the Soviets will do. These people prefer, instead, a kind of escapism, a program based mostly on sentiment: Nuclear war is bad for children and all other living things. No kidding.

The sentiment is understandable. People were scared to death by the gunslinger rhetoric that initially came from the Reagan administration. Talk of limited nuclear war, of demonstrating nuclear weapons, are the sort of stuff that makes for nightmares. Then, too, the world seems to be going to hell in a handbasket. The British are fighting the Argentines and the Iranians are fighting the Iraqis and the Israelis are fighting the Palestinians. And of course, there is always Afghanistan and Northern Ireland and South Africa. It's enough to make you want to pull the blankets over your head.

But neither that nor wishful thinking about nuclear disarmament will do the trick. The world is a nasty place, full of nasty people and nasty countries, and while it is one thing to try to change that--to become involved in issues such as nuclear policy--it is quite another thing to forget that we are not alone, that we have real enemies and that they, like us, are armed to the teeth. This is what the audience that watched "The Atomic Cafe" seemed to ignore. It was watching a farce. And I was watching a tragedy.