Listen too hard to right-wing futurologists - people like Charles Murray and Nicholas Negroponte - and you'll develop a terror of poor young men: the hordes of teenage hoodlums and sink-estate crack-heads who are somehow going to destabilise society from the bottom up. These are the Dangerous Classes; the types from whom affluent middle-aged men - men, I suppose, a bit like Charles Murray and Nicholas Negroponte - are going to be forced to protect their homes by installing iron shutters and flashy new security systems.
But maybe they've got it all wrong. Perhaps they've been looking for trouble in the wrong place. Perhaps there's a newer, more potent source of disaffection and delinquency rather closer to home. Those men in ties by the water cooler, with mortgages and wives and little places in the suburbs. Those fortysomething women in business suits, smoking a bit too much and frowning over a page of accounts. Maybe this lot are the new underclass.
In the last week, a number of troubling statistics have suggested that if you're a professional over 40, you might as well chuck it now. That's right - go home, draw the curtains, and fall asleep in front of Fifteen to One with the sound turned down. The scrap heap, it seems, is accepting new residents at a younger age than ever before.
The number-crunchers at the career management and outplacement consultancy Sanders and Sidney have discovered that in the last couple of years, the average age at which British senior managers are made redundant has fallen from 48 to 46. And 42-year-olds who find themselves unexpectedly jobless are more likely than ever to remain in the benefits queue for good. When you bring other, more long-term observations into the frame - the number of over-fifties in work dropping by a quarter since 1979, for instance - it suggests that a major demographic change is on its way. In a few decades time, you may be considered past it at 30.
These statistics probably don't herald a future quite as nasty and ageist as the one depicted in Logan's Run - where everybody lived in a plastic dome and got ritually incinerated on their 30th birthday - but they do imply that employers are placing more and more value on the youth of their workforces. Age and experience are old hat. Why hire someone who's ancient enough to have figured out that there are far more important things in life than work rather than some pack-fresh young thing who is willing to parrot middle-management jargon about best value and upsizing as though it actually meant something, and who might actually get a kick out of staying late at the office? Who wants Victor Kiam when you can have Martha Lane Fox?
The downsizing mania of the Eighties ushered in the increasing acceptability of sacking middle-aged employees. Cutting out dead wood, it was called, and anyone who performed a little lamely during the paintball session could expect to find a letter waiting on their desk on Monday morning. These days, casualties of this process enroll for executive restart classes and are shown how to write a CV and send an e-mail. Which is helpful enough, but they'll never be true members of the digerati. They'll never be comfortable with the idea of being a portfolio worker who touts for three-week assignments and piecework. You have to be young to find that idea appealing. So they pine for their company car and their index-linked pension, but are increasingly unlikely to claw their way back to another stable desk job in another firm.
But what will happen to those who are old enough to know better? Not much, probably. Which is, of course, no way to run a healthy society. Exclude the middle-aged from the workplace and you may well end up with a world in which fortysomething hooligans will go cruising the streets looking for rich teenagers to smack about with their golf clubs. Pringle-sweatered Dire Straits fans with a nasty grudge against the affluent young, blowing their redundancy packages on crates of Stella Artois, a couple of tickets to Cats and a subscription to Sky Sports. Middle-aged, socially excluded, humiliated and looking to get their own back.
And that's a recipe for real social disaster, one much more divisive than any of the hackneyed dystopias constructed by Murray or Negroponte, all warmed-up 19th-century eugenics mixed with a bit of second-hand sci-fi. Take away Mondeo Man's company car, and he's just a bloke who's incredibly angry about having bought a house that's not within walking distance of a supermarket. And that's the kind of dangerous resentment that causes people to go on shooting sprees in burger bars - where, of course, all the kids hang out.