BARRY SHEERMAN is a brave man. At the weekend the hitherto impeccable Blairite MP said that the hunting ban is being used by some colleagues as revenge for Margaret Thatcher’s pit war. “I hated the way that Thatcher rolled over minority opinion like the miners. I never wanted to be like that, and I think people may come to feel that we are . . .” Some , he said, genuinely believe hunting is cruel, but others just want to get even with a perceived toffocracy. They “are frustrated that they can’t renationalise the top 100 companies, so they say, let’s get rid of foxhunting”.

This rueful admission of class war is interesting for several reasons: particularly the link with the miners. A recurring cry of those who favour a hunting ban has been that the countryside marchers are hypocritical to cite loss of livelihood because they “never raised a squeak of protest over apartheid, or when miners and steelworkers were suffering”. Yet, like most of the insults traded over hunting , this is a crass generalisation. I know a good few people who oppose the hunting ban but who have also passionately opposed greater ills, supported Amnesty for decades and backed the miners. Pits and steelworks are often close to open countryside; miners follow hunts. Society, in this small country, is far more complicated and far more intimately overlapping than is suggested by the savage simplicities of the current debate.

But precisely because of those overlaps, the problem is wider than “class war”. There is a cancer of oversimplification, generalised insult, demonising and polarising. It afflicts every dispute from Iraq to education. It uses a sour, shorthand stereotyping that is fun in comedy acts but death to serious debate.

Take the hunting issue first: a cacophony of nasty voices rises, not arguing about pest control but shrieking “Toff!” and “Townie!” Listen to Rod Liddle, on the “forelock-tugging menagerie” of countryside marchers; to Suzanne Moore sniggering at the Parliament Square violence as “concussed foxhunting ladies bleeding on to their upturned collars”. Hear George Monbiot, absurdly insisting that the “residual power” of the Norman barons must be crushed: “This isn’t about animal welfare . . . by taking on the hunt, MPs are taking on those who ran the country for 800 years.” Hark at Stephen Pound, MP, informing the Today audience that “braying Hooray Henries” called Piers will be defeated: “We’re going to go after their 4x4s, ban pashminas — anyone with a contrasting silk lining on their suit, anyone who’s called Ralph, we’ll go after them.” He was sort of joking; but he is an MP, not a stand-up comic.

Remember the Deputy Prime Minister, damning the “contorted faces” of those who disagree with him; wince at Tony Banks, on a Radio 2 debate with Janet George, of the Countryside Alliance. She declared that she might carry on hunting, whereon the barely honourable member sneered. “I hope you can find a horse big enough”.

The other side are pretty damn rude, too, and almost as moronically prone to generalisation. They build up a cartoon stereotype of “townies”, ignoring that some country people hate hunting; they create fantasy enemies who live in Islington and drink cappuccino, or have straggly beards and vegan sandals. Beneath this weight of caricature the argument sinks from sight. Similarly, discussions about education routinely collapse into intemperate abuse about “snob” private and grammar schools versus the “yobbish” comprehensive. Even the serious matter of the Iraq dossier turned into a testosterone-fuelled dogfight as Greg and Gavin’s gang squared up to Tony and Alastair’s, with all the calm rationality of a clash between William Brown’s Outlaws and the Hubert Gregg mob.

More and more this feels like a nation of bitter, insecure little tribes avid for bones to snarl over. Insults fly through the air: Snob! Trendy! Leftie! Tory Boy! Townie! Peasant! White-van man! Luvvie! Tree-hugger! God-botherer! Hack! Fat cat! Frump! Slapper! Lout! D-lister! It is as if, banned by law from uttering racial abuse, we seek to define ourselves by finding social, economic, pursuit or belief groups to despise. If public discourse is anything to go by, Britain is not so much a Big Tent as a sackful of enraged ferrets.

How did we get here? Shaw said that the moment an Englishman talks “he makes another Englishman despise him”, but that was in 1916. Since then, much has brought us closer. Wider education helped, as did two world wars. Officers and men saw one another’s humanity, and huge communal efforts such as D-Day made diverse trades and classes grateful to one another. The Sixties helped, as Cockney hairdressers became stars and Liverpool lads were courted by royalty. Social fluidity rose, as fewer jobs and pastimes were associated with birth: posh kids discovered football, poor kids went to Oxford. The media — today addicted to sneery stereotyping — offered windows into different lives in a benign, interested spirit. Today they are more likely to give us Jade Goody to jeer at than Fred Dibnah to marvel at. But in the Seventies, I can honestly say that I grew up and worked in an atmosphere when it felt more important to assess people as individuals than to pigeonhole them by accent, background or the style of their collar.

That feeling is rarer now. Tittering style-mag stereotyping has combined with arrogant politics to fuel a culture of boorishness. The new tribalism is a screen, disguising from each of us the awesome fact that every one of the others is a feeling, unique and precious human being. You hear its grating voice when the Home Secretary greets the suicide of a prisoner in his care — albeit Dr Shipman — with a celebratory promise to “crack open a bottle”. You hear it when Billy Bragg sneers at an MP his own age — 44 — for wearing a suit and tie “while I’m sitting here in my Clash T-shirt”. You hear acid scorn in almost every word about hunting, taxation and education, and in almost every utterance of Alastair Campbell.

It is hateful. You have to block your ears and think of some talismanic figure of preternatural politeness: John Julius Norwich, perhaps, or Bob Battle, the farmworker who lived next door, or Mother Teresa, or my dad. It’s either that, or climb on the roof and shout through a megaphone like a giant Mary Poppins: “We’re not at home to Mr Rude!”

Join the Debate at comment@thetimes.co.uk

Times Recommends

• In the real world, the public sector must pay
• Playing politics in a land of double Dutch
• Be like the plinth people: not set in stone