Standards really are slipping. In 1991, Peregrine Worsthorne was memorably dismissed as editor of the Sunday Telegraph midway through the consumption of a succulent poached egg. Kim Fletcher, newly expelled from the Independent on Sunday, didn't even have time to finish the banana on his desk.

I know the face of Fletcher's executioner. It was the same Brendan Hopkins, Tony O'Reilly's man-about-London, who four years ago summoned me to his office "for a drink" and handed me not a glass but a three-paragraph press release headed "announcement".

It informed the world that I had resigned as editor of the Independent and recorded the gratitude of the company for my "stewardship". It even mentioned that "during his [my] tenure circulation has improved to a peak of 300,000". Hopkins told me, however, that "a different approach" was needed to secure the next 50,000.

My successor indeed made a 50,000-copy difference to the circulation - but in the wrong direction. It hurtled back to 250,000 within six months. Today the Independent sells 225,000 copies - a figure improving under the benign influence of O'Reilly's money and a talented editor, Simon Kelner.

I see that my cherished copy of Hopkins' "announcement" also has something handwritten across the top. It says: "For the attention of Bob Storer." Lest future historians puzzle over this strange inscription, let me at once explain it. Bob Storer is a media lawyer who specialises in negotiating severance terms. His name was given to me by Janet Street-Porter, who left Canary Wharf a few weeks before me when Kelvin MacKenzie insisted that Live TV's topless darts be given intellectual structure by a few rounds of bottomless rugby.

This is not the only reason I like Street-Porter. I liked the way she sat behind her table, like a stilt-walker resting at the edge of a carnival, cursing the considerable difficulties of delivering the Mirror Group's Live TV ambitions with no outside broadcast facilities. I liked the way she irritated the bulbous nose off MacKenzie, who constantly roared that she was "always on fucking holiday".

I also admired her television work at LWT and the BBC, where she found and projected new voices and where, again and again, she was willing to take the risk of being called a fool. Street-Porter, who is as serious in her concerns as anyone I know, is no fool.

She must not, however, make the old mistake of thinking that the bar-room merriment that has greeted her appointment ("Send in the clowns" - Daily Telegraph editorial; "She couldn't edit a bus ticket" - K MacKenzie; "You laughed hysterically, didn't you?" - Roy Greenslade, Guardian) guarantees her success. The mockery will stiffen her subversive nerve, but at the BBC her conviction that she had been held back by sexist male mediocrity eventually blinded her to her own shortcomings - erratic focus and an inability to organise and inspire those who don't naturally dote on her.

But nor do I think that Street-Porter is bound to fail. True, she could not be more different from the richly talented newspaperman she succeeds, but it is possible that, at the age of 52, she has outgrown her weaknesses without losing her creative drive. True, too, the Independent on Sunday is hobbled by an editorial budget (£3 million a year) that would not keep the Sunday Times in book serialisations, but presumably O'Reilly will back his latest hunch with money. True, also, she will soon find that mere celebrity doesn't sell newspapers - look at Rosie Boycott's Express, the Observer under Will Hutton or even, in a different era, the New Statesman under Richard Crossman.

But the real point about Street-Porter is whether her kind of ideas can be successfully channelled through the medium of a Sunday newspaper.

What struck me about her manifesto in last weekend's paper (apart, it has to be said, from the ugliness of its prose) was how much it has in common with the vision of Michael Jackson, chief executive of Channel 4, set out in the following day's Guardian. Street-Porter imagines a "polymorphous journal for a multicultural society"; Jackson took as his primary point of analysis the new British melting pot and said that he wanted to create "talking point television, television that creates ripples in the culture".

Jackson's statement is taken as the last word in creative radicalism, whereas Street-Porter is ridiculed. This is not only because Jackson is a quietly spoken man and Street-Porter a gabby woman; it is because television has been able to diversify its cultural personality and range in a way that broadsheet newspapers, so far, have not.

It may be that such a task is impossible, alien to a medium built around 19th-century ideas of public discourse, but I doubt it. One day, a cultural radical is going to reinvent a British national newspaper successfully; if not, newspapers are in even more trouble than they seem. Maybe, just maybe, this reinventor will be Street-Porter.

How can she maximise her chances? The easy part is to lampoon the scoffers. Then she should think television: independent producers, second-run rights for American material, interactive relationships with readers, marketing tie-ins and the rest. It may cost more money and time than O'Reilly is willing to place at her disposal, but she has nothing to gain from running with anyone's instincts but her own. And I doubt that she has lost Bob Storer's number.

The writer is professor of journalism, Cardiff University