Here’s a sad little note to temper the cheer: a study published last week, by University College London, concluded that children who are let out to play unsupervised grow up to be healthier and more sociable. Healthier because, it was found, children without adults in tow burn up more calories in heightened energy, thus warding off obesity, and more sociable as a result of independence and self-reliance – benefits whose loss, says the leader of the study, Roger Mackett, carry many and grave implications. What makes this so sad is not that the professor is right; it is that there is scant chance of anyone taking a blind bit of notice.

Certainly the Government won’t. The “Children’s Plan”, as unveiled by Ed Balls earlier this month, is bent on increasing adult involvement in children’s lives: parents are to be encouraged to take a more active role in their children’s education, there are to be more hands-on “support services” (run by grown-ups), greater access to “high-quality cultural activities” (led by grown-ups) and the mass construction of “supervised adventure playgrounds” (spied on by grown-ups; Mr Balls appears serenely unaware of the oxymoron that is a “supervised adventure”).

To be fair, the Government is only playing to established, if relatively recent, public demand; at least among those old enough to vote. The contemporary perception of good parenting is to be as hands-on as the days are long, from the diligent morning school run to chauffeuring the rounds of after-school activities, even sitting in to watch whichever dance or music or sports class the parent has deemed to be a suitable use of his or her time; if the parent is willing to drive to, say, jazz ballet lessons but not to martial arts, then the child’s interests are determined for him. How could he even get to the martial arts? On a bus? On his own? Don’t be daft.

The University College study found that nearly half of children between 8 and 11 are never allowed to leave the house alone. Anxious, upright parents, among them those perfectly prepared to rail against the intrusion of CCTV or identity cards in their own lives, are buying into the equally new notion that it is part of their job to run 24/7 surveillance on their own children.

Privacy, it has been decided, is no longer a luxury that children can be afforded. I do not believe that my mother would have dreamt of reading my diary; I know that I did not read my daughter’s. Yet I recently heard the mother of a 14-year-old patting herself on the back for having cracked her daughter’s e-mail password, such that all the girl’s mail, in and out, is covertly copied to her mother’s PC. “Well,” she said, to much nodding agreement, “These days . . . you can’t be too careful, can you?”

Yes, you can. I further think that the biggest difference between “these days” and better days is not an increase in risk but a huge increase in artificially stimulated alarm, boosted by prurient gawping at the occasional, albeit dreadful, tales of a Sarah or a Madeleine, whose agonies handily provide an excuse to impose a constant, intrusive and ultimately counter-productive adult presence upon children who deserve better.

Let us have a bit of a Hovis-commercial moment and revisit the sepia of less modern childhood. No child ever thought the school holidays too long; no parent ever whined about the pressures of filling them – empty days were, frankly, none of their business. Ours began with the knock, “Can Carol come out to play?”, and ended, as instructed before we scarpered, with the muddy return come teatime. Ish.

If our parents gave thought to the stranger danger of abduction and murder, they knew the chances: there were, on average, six each year. There still are. We didn’t have “groomers”, but we had flashers – and let me tell you, when left to their own devices, there is no disdain quite as withering as that perfected by a bunch of nine-year-old girls faced with yet another silly willy.

Far more important than our interaction with smut and threat, however, was our interaction with each other. Small people, given their freedom, form small social orders: complete, valid microcosms of what is to come. Neither Enid Blyton’s cosy Famous Five nor, at the other extreme, William Golding’s Lord of the Flies were entirely wrong; most such orders, when allowed to flourish, fell somewhere between the two. Leaders emerged, as did the led. Courage, dishonesty, loyalty, enterprise, rejection, consensus, diplomacy, each was experienced in a way that they simply cannot be under the permanently vigilant eye of the adult who intercedes with his own judgment – “That was your fault, Jill, say sorry to Jack”.

Those who seek by their constant presence to control childhood are stealing it from its rightful owners: children. It would, of course, be ridiculous to suggest that they be left to run feral. But there is a difference between intervention when it is needed and interference as a default position.

If half of our children are not allowed out alone until they are 12 or over, it is hardly surprising that one of two things then happen: either they emerge into streets so strange and fearful that they find structure and comfort only in gangs and weaponry, or – less dramatically, but in its way just as dismal – they join the thousands who, in this holiday week, will slump on a couch until their parents answer a question they have never learnt to answer for themselves: what are we doing today?

Of all the gifts, over all the Christmases they have enjoyed, it might well be that none would have been as enduringly precious as a charming little bauble of carefully crafted neglect.

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