O frabjous day! This should be a bank holiday, surely, in celebration of what social media is calling #piggate and the official media is studiously ignoring. Tick whichever conspiracy theory you like regarding that media response. But let’s face it, no one can get any work done while we could be discussing whether the prime minister did “put a private part of his anatomy” into the mouth of a dead pig during an initiation ceremony while at Oxford. Which is a university, apparently. This allegation is contained in a new book Call Me Babe … sorry, Call Me Dave, by Lord Michael Ashcroft and Isabel Oakeshott, which is now being serialised in the Mail.

Twitter is, of course, in spasms of ecstasy. We want the story to be true, and the politics, as well as the pig, are fascinating. Ashcroft is a former Tory donor. Oakeshott is former political editor of the Sunday Times. The Mail is a Tory paper.

Ashcroft is out for revenge and the book is packed with other allegations, but frankly no one gives a damn. The claim that Cameron may have smoked dope with the journalist James Delingpole while listening to Supertramp may be a crime against humanity but it is the pulled pork issue that has us preoccupied. I have always defended Cameron’s and Osborne’s right to have taken drugs, if they have, but this new story, if true, would be much harder to excuse. I mean, we have all done stupid things while off our heads – just not with dead heads. It makes old Corbyn having had an affair with a human woman, which the papers were trying to sell as the other big political scandal of the week, look pleasingly vanilla and vegetarian.

Our identification is with the pig. The dirty little secret at the heart of our establishment may not be this one at all

There is said to be photographic evidence of “the act” (but notably it has not been produced), an incident that first came to light when it was mentioned at a business meeting in 2014 by an MP. When our own Nostradamus Charlie Brooker wrote an episode of TV drama Black Mirror in 2012, about a prime minister forced to have sex with a pig, the politician was being forced into it for a noble cause. In these allegations the act was apparently performed with the pig’s head resting on a colleague’s lap, and functioned as a means of entry into the notorious Piers Gaveston society, supposedly posher than Bullingdon (although friends deny Cameron was ever a member of the Piers Gaveston society). These initiation ceremonies are often part of bonding in all-male groups. They can involve horrible gang rape in US campus frat societies. Maybe a pig is tame. Maybe the pig is not even real. But what is being exposed is the cabals of the rich and powerful who protect one another. The pig is the dead cat of the Lynton Crosby theory that was once explained by Boris Johnson, another Bullingdon member. By throwing a dead cat on a dinner table, no one will talk about the issue in hand, which could indeed be how a man like Ashcroft has so much sway, how democracy is bought and sold by these sometime non-doms. Substitute dead cat for dead pig here – or indeed go back to Hunter S Thompson, who once told us while on the campaign trail that this was one of the best tricks in politics, and that he’d seen it used by Lyndon B Johnson. Johnson suggested his opponent had a penchant for “carnal knowledge of his own barnyard sows”. His campaign manager said no one would believe it. “I know,” Johnson replied. “But let’s make the sonafabitch deny it.”

While George Osborne is out of it in China – where we have just secured important pork markets and pig semen deals (I’m not joking) - Cameron can only hope this goes away. It won’t.

It won’t because the hamminess of Cameron himself is ever present; it won’t because there are still a thousand brilliant jokes to be made (“bae of pigs” is just the start); it won’t because this image is now lodged firmly in our minds. “The creatures looked from pig to man and from man to pig and it was impossible to say which was which,” wrote Orwell, in Animal Farm. Our identification in this story is with the poor piggy, because the dirty little secret at the heart of our establishment may not be this one at all. We already know there is an entitled class that feels that normal rules don’t apply. It’s just part of the full English.