What a shame the senators weren’t treated instead to The Celluloid Closet, from which they would have learned that the defaming of gays on film has a long and ignoble tradition. This smart, ruefully funny documentary, based on a groundbreaking book by the late Vito Russo, examines Hollywood’s depiction of homosexuality from the silent era to “Philadelphia,” decoding a century’s worth of lethal stereotypes and sly subtexts.

In a frothier vein, perhaps the politicos should check out The Birdcage, Hollywood’s long-delayed remake of the 1978 French farce, “La Cage aux Folles.” On second thought, they might not be amused, for the butt of the joke is a reactionary senator (Gene Hackman) who proudly waves the flag of homophobia. Most everyone else will be tickled pink by this sleek Mike Nichols remake. With Robin Williams as the nightclub owner Armand (he’s now Jewish) and Nathan Lane as the tempestuous drag queen Albert, “The Birdcage” should confirm the property’s foolproof commercial appeal, which has little to do with sex and everything to do with the seemingly irresistible spectacle of men in dresses. From the brilliant “Some Like It Hot” to the laborious “To Wong Foo Thanks for Everything Julie Newmar,” Hollywood has embraced cross-dressing as the safest way to pitch gayness to a mass audience. Drag queens are the cinema’s favorite naughty pets, harmless if not quite housebroken.

What’s striking about “The Birdcage” is how little it’s changed in 18 years. Sure, the setting has been revamped to Miami’s South Beach. And writer Elaine May has liberally sprinkled in topical references from gays in the military to Bob Dole. Otherwise, Nichols carefully follows the classical-farce footprints of the original, in which the middle-aged gay couple are forced to conjure up a straight faade to facilitate the marriage of Armand’s son to the daughter of the gay-bashing, anti-Semitic senator.

It worked before, and it works again, though for the first hour I thought Nichols had blown it. Why wasn’t he having more fun with the material? Nichols and May have updated their surroundings, but they haven’t rethought their heroes. Old swish stereotypes to begin with, they make even less sociological sense in South Beach two decades later. Babyboomers Armand and Albert behave in the queenly, asexual style of an older generation of gay men. Of course we know the real reason for this: two men kissing is a box-office no-no.

If Nichols and May are out of touch with gay life, they do know a thing or two about comedy. The farcical wheels Nichols has been slowly oiling shift into high gear when the senator and his genteel wife (Dianne Wiest) come to dinner to meet the prospective in-laws. Suddenly, “The Birdcage” takes supremely silly flight. The hysterical Lane dons his dowdy, Republican grande dame drag to enchant the senator; Williams squeezes himself into a manly black suit and the flouncing manservant (a very funny Hank Azaria) almost blows the game when he serves up soup bowls decorated with naked Greek boys doing ancient Greek things to one another. The movie’s method, and its message, are as old as comedy itself, as the lords of misrule rout the spoilsports who would try to legislate love.

“The Celluloid Closet,” made by Oscar-winning filmmakers Rob Epstein and Jeffrey Friedman,makes a great companion piece to “The Birdcage,” whose prissy Albert is an uncloseted descendant of the movie prototype here called The Sissy–that sexless, effete comic second banana played by the likes of Franklin Pangborn and Edward Everett Horton throughout the 1930s. Narrated by Lily Tomlin from a text by Armistead Maupin, the film spices its treasure trove of clips with trenchant interviews with Tom Hanks, Gore Vidal (who explains how he worked a homosexual backstory into his screenplay for “Ben Hur”) and Susan Sarandon. When gay men and women weren’t invisible, they were usually presented as evil: lesbian vampires, the sinister housemaid in “Rebecca,” the faceless, predatory Sebastian in “Suddenly Last Summer”–all characters who must pay with death for their depravity.

After the breakthrough of “The Boys in the Band” in 1970, Hollywood gingerly began to catch up with the times. But it still falls to the independents to rectify the damage, with such films as “Parting Glances” and “Go Fish.” While Hollywood makes the occasional timidly honorable movie about homosexuality, the independents make movies–good, bad and indifferent–about people who happen to be gay. It’s taken almosta hundred years of cinema to reach this sane matter-of-factness. But the battle isn’t over, not as long as Hollywood acts like a scared politician and politicians act like bullies in a B movie.