Wow, lesbianism sounds so cool in Katy Perry's I Kissed a Girl, which made it to No1 on Sunday: “Us girls we are so magical/ Soft skin, red lips, so kissable/ Hard to resist so touchable/ Too good to deny it.”

But despite the refrain of “I kissed a girl and I liked it”, Perry is careful to insist that this is just a bit of lesbian tourism. “Ain't no big deal, it's innocent” she says. “I hope my boyfriend don't mind it,” she adds. “Don't mean I'm in love tonight.”

The song has been attacked by conservatives for promoting homosexuality, but their ire is puzzling - in the end Perry opts for heterosexuality and skulks away from full-time lesbianism.

Still, it has generated some star-making controversy for her. In another song, Ur So Gay, she sings, presumably at a man: “You don't eat meat and drive electrical cars... You need SPF45/ Just to stay alive/ You're so gay and you don't even like boys.”

There's nothing original about her gay swaggering. Straight culture has been fetishising and flirting with gay culture ever since drag become primetime entertainment. If a TV show is flailing, a straight character will “experiment” with homosexuality for a ratings hit. The Russian pop duo Tatu exploited lesbianism much more saucily than Perry.

What's striking is that the instigators of this pop culture same-sex flirtation are proudly straight. Guy Ritchie's new film RocknRolla, out on September 5, is relentlessly hard-knuckled and hetero, but at its heart obsessed with man-on-man action. Not only is there a gay gangster who has sex with one of his cohorts, but his homosexuality, and gay sex, is laboured over in a determinedly laddish way. Poof this, queer that.

The film is dripping with gay fear and gay desire: looks of sheer disgust at the idea of gay sex, grudging acceptance, lingering shots of one muscular character clad only in tracksuit bottoms. Is this Ritchie's mea culpa for his perceived homophobia, as recently relayed by Madonna's brother Christopher Ciccone? If so, it's possibly the world's first anti-gay gay movie.

Both Perry's song and Ritchie's film seem to want to have a little gay slap and tickle, but be home in Straightville in time for tea. Beneath their flirtation lies the same patronising dismissal in one of Perry's lyrics: “Ain't no big deal”. Homosexuality - disposable, just a phase - doesn't merit a hit pop song where the girl kisses a girl because she's actually gay. That would be radical. Christian groups shouldn't be protesting against I Kissed a Girl, but embracing it as a new theme tune.

Tim Teeman is arts & entertainment editor of The Times

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