In this case, though, there were no shock front-page exposes splashed across the tabloids, no middle-market accusations of moral turpitude, no stinging denunciations of male sexuality by harpie columnists, no prim disapproval from the broadsheets. All that happened was that a couple of newspaper diaries referred to the story. Mr Mandelson later cancelled a return visit to Brazil, citing ministerial commitments here.
There were, I suspect, four good reasons for this: (1) fear of losing in the libel courts; (2) fear of Alastair Campbell; (3) fear of appearing anti-gay (homophobia-phobia?); and (4) the allegations were made in Punch, and nobody seems to take that magazine remotely seriously anymore.
At which point, I must declare an interest. I edited Punch between 1989- 92, when the magazine was closed down by its then-owners, United Newspapers. For most of my three years in the job, I had to live with constant sniping from ex-editors, ex-staff members who thought they should have been the editor, and a couple of eminent journalists whose broadsides oddly omitted the fact that they had applied for my job and failed to get it. Which is why I do not intend to attack the staff of Punch for turning a magazine that was once a by-word for civilised, literate humour into a muck-raking scandal-sheet. Because I can see exactly why they're doing it.
Consider the alternatives. You could run Punch in the old style, a weekly magazine filled with columns by much-loved middlebrow celebs, interspersed with amusing cartoons ... and lose an enormous amount of money, because this is a magazine for which there is no conceivable need. All the columnists one would hire are already working for newspapers: why would anyone pay every week to read their off-cuts?
This much was obvious when I got to Punch almost a decade ago, and the point was underlined in 1996, during the publication's relaunch by Mohammed Al Fayed, under the editorial guidance of Stewart Steven and Peter McKay. Huge sums were spent to hire big-name writers and recreate the old ambience. Punch was for a while the juiciest gravy-train in British journalism, and the result was a lavishly appointed magazine that cost Mr Al Fayed several million pounds, as even with the marketing muscle of Harrods, its circulation was pitiful.
So what else could anyone do? Well, I always felt that there were two ways to go. The first, for which I fought at great length, was to make Punch a monthly. This meant abandoning 150 years of weekly publication, but by coming out once a month we could hugely increase the quality of our editorial and design, retain the title's upscale image and produce a literate, witty men's magazine (the traditional readership was always overwhelmingly male) that would appeal to both readers and advertisers.
Sadly, it would have been a disaster. The past few years have proved that there is a massive market for men's magazines, but only if they've got crumpet, cars or computers on the front. I'd love to believe that there are male readers out there yearning for intelligence and fine writing, but the truth is they'd rather gawp at pictures of Cameron Diaz and Denise Van Outen lying around in their underwear.
The alternative was to stay weekly. But no one needs to look at funny cartoons or read mildly amusing articles badly enough to pay for it every week. Punch had to be a compulsory purchase. And the way to make it one, I reasoned, was to go after Private Eye's news content. Dig up dirtier dirt, grubbier gossip and even more secrets from the Street of Shame... and do it twice as often, so that Ian Hislop's mob were forced to play catch-up.
But this was an expensive option, as it would require staff reporters, more section editors and expensive investigations. "Fund us properly," I told United, "or put us out of our misery." It wasn't a choice they found too hard to make.
Six years later, Al Fayed's Punch has done what United's would not. The timing couldn't be better: we badly need a publication willing to savage the rampant hypocrisies of New Labour Britain. The Blair government is attackable from Left or Right, riddled with intrigue and beset by at least as much sleaze as its Tory predecessors. Institutions from the BBC to British Airways are filled with oppressive management and discontented staff, as are most of Fleet Street's papers. Yet the official Opposition is virtually non-existent, there is a squeamishness within the media about attacking the Government with the zeal once applied to the Tories and few dare provoke the men who (mis)manage our own industry.
Punch is trying hard to make the best of its new remit. As well as the Mandelson cover story, the latest edition contains a piece by Annie Machon, the partner of the renegade MI5 spy David Shayler, a fascinating insight into life as an enemy of an embarrassed and vengeful state. There is a strong story about a series of unsolved murders in Ireland and the media gossip - including barbs against this newspaper - is, if anything, stronger than the Eye's.
It has to be be said that it seems to have an obsession with Mandelson: this is the second long piece on him this year. The other obsession is Associated Newspapers - Punch's editor, James Steen, hails from there - and the magazine previously lost a court case against the late Lord Rothermere after writing about his first wife, "Bubbles".
In recent weeks the magazine has tried to take on cocaine use at Virgin Radio and earlier this year did very well out of simply looking in the bin bags outside banks.
Yet Punch is struggling. It only appears on a fortnightly basis, does not publish an audited circulation figure and its advertising pagination is painfully spartan. Having lived large in the early Al Fayed days, the present Punch team must now be subsisting on the most meagre of financial rations.
So what's gone wrong? Well, the the magazine's pursuit of scandal is now so overwhelming that humour has been almost entirely banished, barring a few very poor cartoons. The result is a publication whose snide tone is unleavened by laughter, while the better parts are peppered with too many items based on sneering rather than substance.
More damagingly, Punch has become a pot calling other kettles black. Its editorial independence is hopelessly compromised by the fact that its owner is precisely the sort of person whose activities - commercial, political and personal - might quite reasonably have once been expected to be the subject of its investigations. Finally, it faces what may be an insoluble difficulty. The traditional audience for Punch don't want to buy the new magazine. And the people who might be interested in what it now has to offer won't be attracted by a magazine called Punch. A title which ought to be as prestigious a property as The New Yorker or Vanity Fair has, through decades of mismanagement, complacency, and then panic changes, become more of a burden than a blessing.
Lacking the sort of gentle, consistent nurturing that has seen The Spectator rise from the ashes over the past 15 years, Punch's image is blurred, its market either indifferent or confused. Six and a half years ago, we said goodbye with a cover showing Mr Punch and his loyal dog Toby walking off into the sunset. Perhaps they should have stayed there.
David Thomas was editor of `Punch' from 1989 to 1992