`MOTHERS of America/ Let your kids go to the movies!'' This line by poet Frank O'Hara was written tongue-in-cheek in the 1950s. But it recognizes the unique American cultural involvement in film. Since the turn of the century the movie house and the silver screen have acted as an important agent and repository of American myths, symbols, and history: ``Casablanca,'' ``Citizen Kane,'' ``The March of Time'' newsreels.
That repository is in danger. Until acetate film came in the '50s, movies were shot on nitrate-based film which disintegrates rapidly. Of the 21,000 feature films, 120,000 shorts, and 30,000 newsreels made before '50, half are lost, most because of nitrate.
The kind of film classics mentioned above are out of danger - though a cheap coloration process introduced in the 1950s has faded originals of films like ``South Pacific'' and ``Rebel Without a Cause.'' Gone are Eric von Stronheim's ``Greed,'' Norma Talmadge's 1927 ``Camille,'' and Laurel and Hardy's ``The Rogue Song.''
But it's the 100 million feet of short takes, home movies, and historical shots that are wasting away in far-flung US archives. These need to be copied. The National Archives copies about 4 million feet a year - not enough.
The problem, as usual, is money and logistics. Copying black and white film from nitrate to acetate costs $2 a foot; color film costs three times as much.
Upon finding that no original of Stanley Kubrick's ``Dr. Strangelove'' now exists, several Hollywood directors formed the Film Foundation. The group hopes to raise $30 million for film preservation. The major studios ought to contribute to this fund. With a gross of more than $2.2 billion dollars so far this year (``Pretty Woman,'' $149 million; ``Teenage Mutant Ninja Turtles,'' $127 million) that's not asking a lot. Yet as Steven Spielberg notes, the studios have offered more good wishes than cash.
In more than one way, perhaps it's the word that endures.