Johann Hari

As a country, we can spend countless hours discussing rival teams of men kicking a piece of plastic into a net. But we are all supposed to be shame-faced about discussing the fantastically complex dramas called Reality TV. Well, I'm not.

Have the sinews of racism and snobbery been more truthfully traced than in the showdown between Shilpa Shetty and Jade Goody? Has the reality of sexism in the workplace been laid out more rivettingly than in Alan Sugar's annual picking of amiable, malleable men over competent, dynamic women to be his apprentice? Now this glorious genre has dramatised the clash within British Islam – between secularisers and fanatics – with the same concision.

Reality TV has long shown a face of British Islam that contrasts with the murderous smirk of the Tube-bomber Mohammed Sidiq Khan. It gave us Chico Slimani, the buff, rippling ex-Chippendale who blagged his way through The X-Factor; Kemal Shahin, the smart, tart young gay man who dominated Big Brother 5; and Saira Khan, the feminist entrepreneur from The Apprentice who refuses to let her religion be hijacked by "bearded old men from the Middle East". They represent the first fragile shoots of a secularised Islam that – like most Christianity and Judaism in Europe – can be shrunk until it is a matter of custom and private conscience.

But on our reality TV shows, this has always been a one-sided fight. Fundamentalists, by their you're-all-damned nature, are not inclined to take part in reality TV. Until now.

If you were told the biographies of Big Brother contestants Mohamed Mohamed and Alex De-Gale, you wouldn't find it hard to guess which one is the fundamentalist. Mohamed was born in Somalia in 1985. When he was five years old, he saw his mother being held at gunpoint, and thought she was going to die. Since then, he has spent most of his life fleeing from one civil war to another – until, finally, he was granted asylum in Britain. De-Gale was born in the same year in south London, to black British parents. She is now a lithe accounts executive with high cheekbones, short skirts, a BMW, and a seven-year old daughter she brings up on her own.

You guessed wrong. They wouldn't use these terms, but Mohamed became a convinced secularist on the run from Somalia, while Alex learned a Wahhabbi interpretation of Islam on the streets of Tottenham. This emerged, as everything does on Big Brother, through a thicket of trivia. Mohamed's birthday fell a week into his stay in the Big Brother house, so the producers threw him a party, and let him pick the theme. Remembering a fun night he'd had at university, he said he wanted the male housemates to dress as women, and vice versa. Everyone cheered and howled for alcohol.

Except Alex. "First and foremost," she said, "I am a Muslim." And that meant the idea of a man dressing as a woman "made me feel sick". Jabbing her finger and shouting, she said to Mohamed: "Tell it to Allah [that] it's all in the name of fun. It's bad enough that we drink and smoke ... You're supposed to be a Muslim man, someone I can look up to for guidance. You will have my friends and family in uproar. I am disgraced by you ... 85 per cent of the people I know are Muslims. And trust me – the sheer horror they would have experienced ... [You have] disgraced Islam."

"You can't tell me I'm a bad Muslim," Mohamed replied. "I am old enough to be responsible for myself. Don't bring religion into it!" She snapped back: "It is! There's nothing else!" Alex was so enraged she announced she has "gangster friends" and, if she was evicted, "I get to go out [and] see everyone's friends, I get to see their family. I get to do the shit that I wanna do. Pow, pow, pow." This threat wasn't necessarily idle: Alex has a restraining order against her after she waged a "hate campaign" against a former friend.

In that little exchange, you see the contrast between two understandings of Islam. I live in the middle of the Muslim East End, and I see this raw, rubbing conflict being played out every day.

Alex believes that Islam offers Absolute Judgements, immutably cast in stone in the Koran. These are (of course) hellishly patriarchal, since they were formulated by illiterate desert merchants in the seventh century AD. She has been taught there is "nothing else". Later, she explained to another housemate that Islam forbids drinking and smoking. "What can you do then?" he asked. "Pray." That's all. If you see somebody acting in a way your pre-modern system judges to be "sick", is it perfectly moral to threaten to kill them?

Mohamed, by contrast, sees the religion as consisting of metaphors and moral guidance – and he thinks it has limits. There are places it shouldn't go. "She always brings religion into an equation that religion has nothing to do [with]," he said angrily. But what makes this argument even more fascinating – turning it from a scene by George Bernard Shaw into one by David Mamet – is the ambiguities within Alex's character. She howls about the morals of seventh-century Arabia, when they would have her stoned to death. Almost every Islamist I have met has this dissonance running through them. The 9/11 hijackers went to a strip-bar and got drunk before staging their cry for the construction of a Caliphate that would kill them for doing just that. The "moral" vision they believe in is so inhuman even they can't follow it.

So how do we make sure relaxed secularists like Mohamed, Chico, Kemal and Saira beat Alex's wing of Islam? They have answers of their own. They all start with us ceasing to show multicultural politeness towards fanatical theocrats. Saira Khan – who as a teenager was whipped by her father with a coat-hanger for letting her legs show – says we need to call misogyny and gay-bashing by their proper names. Muslims are not a homogenous block represented by the elderly Saudi-trained Mullahs who taught Alex their totalitarian model of Islam.

But we are handing more and more Muslim children over to them to indoctrinate. Faith schools herd the kids of Muslim parents away from the rest of us and pickle them in stale dogmas. Khan – who has spoken at many Muslim schools – says they "encourage segregation and women to be submissive". When I called Kemal, he was even more emphatic, saying: "I would have died in one of these Muslim-only faith schools." There, the Alexes can mass and shout down the Mohameds with the backing of their teachers. (Our oil-addicted foreign policy makes it easier to tell them the democratic society outside is evil.) Yet the Government is not dismantling faith schools – it is building more of them.

So watch that row between Mohamed and Alex again. It is a shouting match – "This is nothing to do with religion!" "Tell it to Allah!" – playing out in a million variations in souqs and madrassahs and Muslim homes across the world. Now that's what I call reality television.

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