South Park is a potty-mouthed series created by two young iconoclasts, Matt Stone and Trey Parker. It features a group of nine-year-old cardboard cut-out pals whose adventures include run-ins with a talking piece of Christmas poo, Jesus, Saddam Hussein and Mel Gibson. The show is both highbrow, it has dissected left-wing political correctness along with Vatican hypocrisy, and lowbrow.

Yes, Paris Hilton once entered a “whore-off” contest with a gay character called Mr Slave. The show is as offensive as it is inspired: the first truly post-PC television adventure. It is also brave. It doesn’t only skewer political ideology, it also aims square at religions. It has mocked Catholicism, Mormonism, evangelicalism and even featured a cartoon Muhammad as a super-hero.

The Catholic League managed to stop a rerun of an episode called Bloody Mary. But now things have become really ugly. Though South Park is broadcast in Britain one episode has never been aired in the UK, and has just been pulled in the US. The show mocked Scientology. In the episode one of the kids, Stan, takes a Scientology “stress test” and does so well he is hailed as the reincarnation of L Ron Hubbard, the science-fiction writer who started Scientology.

Suddenly the child is mobbed. John Travolta shows up. Stan is sent to his room, where he finds Tom Cruise. When Stan tells Cruise what he thinks of his acting skills, Cruise is so crushed to have been dissed by the new prophet of Scientology that he runs into a closet and won’t come out. A chorus of people then implore Cruise to “come out of the closet”. Not exactly subtle. But it’s a cartoon; the episode begins with a disclaimer that none of this is supposed to be mistaken for reality.

In the US all hell broke loose when the episode was broadcast. One of the show’s cartoon stars, an oversexed, overweight African-American chef in the school cafeteria, is voiced by Isaac Hayes, the soul singer best known for singing the theme song for Shaft. Hayes, it turns out, is a Scientologist.

At first he seemed to have no problem with the episode. He told the American satirical magazine The Onion that he often had to defend the show’s edginess: “I told them not to take this stuff seriously. If you do, you’ll get in trouble. Just enjoy it.”

That was January 4. By January 18 Hayes had been admitted to hospital for “exhaustion”, and a friend subsequently said he’d had a stroke. Eight days ago Hayes quit the show, accusing it of religious “bigotry”. (Chef has since been outed as a paedophile, fallen off a bridge, been mauled by a mountain lion and died.) Then the Scientology episode rerun was abruptly yanked from the schedule.

News reports say that Viacom, the company that owns Comedy Central, made the decision. Viacom also owns Paramount movie studios, which has spent a small fortune on Mission: Impossible III starring Cruise, a Scientologist. He denies any connection. Viacom refuses to say why it hasn’t put the episode back on the air. South Park fans have started a petition.

And so we are back where we were with the Muhammad cartoons. Someone somewhere won’t let you see the Scientology episode of South Park. You can go to the Comedy Central website and view it on the internet — the last refuge for free speech. But you won’t see it on television. In a battle between satire and religion, although some deny that Scientology deserves that moniker, religion wins again.

This is, of course, a trivial story in many ways. South Park is preternaturally puerile (though it remains one of the most inspired pieces of sane lunacy out there). There are wars going on. Who cares if one silly episode of a silly series gets pulled?

Well: count me as one who does care. In the mansion of free speech cartoons have an honourable room. You can say things in cartoon form that you could never put into words or enact with real live human beings. You can turn politicians into unearthly creatures; you can portray the powerful as fools and liars; you can mock pretension of all sorts with an abandon and visual wit the written word cannot match. You can create fantasy worlds that make arguments that would be libellous or untrue in other contexts.

In the cartoon in question no one alleged that Cruise was gay. They constructed a scene where he was in a closet and others were urging him to come out of it. And it’s this artful ability to say in cartoon form what you cannot say in any other without a libel writ that makes cartoons irreplaceable.

In the Parker-Stone puppet film, Team America, you get to see Michael Moore explode as a suicide bomber. In the sublime South Park movie Saddam Hussein has a gay love affair with Satan. Cartoons and puppetry, as the classic series Spitting Image proved, can convey truths and explore fantasies no other form can.

We need those truths and benefit from those fantasies. A free society survives partly because the powerful are mocked, and their pretensions undermined. Religions, which guard their own illusions carefully, are particularly ripe for satire. And they should be.

Whenever one human being is claiming to tell the truth about the meaning of life he is making a very powerful claim — and in a free society he also runs the risk of getting a raspberry. Laughter matters because piety begets power.

Orwell once remarked that one reason fascism never took off in Britain was because the sight of a goose-stepping soldier would prompt your average Englishman to giggle. Someone is now silencing the giggles. And our world is a lot creepier because of it.

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