There is a grotesque inevitability about commenting on drug misuse in Scotland. If you were to plot the depressing milestones on a graph, it would have the trajectory of a handcart on its way to hell. I remember the disbelief a decade ago when the Scottish Office Drugs Task Force announced that five-year-olds were to be educated about drugs. It seemed about as relevant as teaching them rocket science.

These days we take our infants’ familiarity with the language — if not the concept — of drugs awareness for granted. “Herod is the worst drug,” announced my son authoritatively before he could spell his name. “It kills babies.” We do not, however, expect our five-year-olds to come into contact with narcotics.

But last week a primary one pupil arrived home from Mossgiel primary school in Dundee with a bag of amphetamine in his satchel. He had found the drug in his classroom work tray, alongside the daubed pictures of dinosaurs and those carefully executed, wobbly sentences that are the five-year-old’s stock in trade. For the time being, we are shocked. But if the past is a predictor of the future, the discovery of drugs in primary classrooms will be almost routine in a few years’ time.

Last week Douglas Ewart high school announced it was bringing sniffer dogs into the classroom in the fight against drugs. We all have schools in our neighbourhoods where cannabis is openly smoked in the playground. I shudder to think how much has been spent in the past 30 years on futile attempts to deal with a problem that is as tenaciously embedded in our culture as mercury in the bloodstream.

Last week it was revealed that since Labour came to power, the number of children with drug problems has risen by 400%. As an endorsement of nine years in office, it’s not exactly ringing, but then none of the other political parties have the solution either. And two cheers for Jack McConnell for his recent stand on rescuing the children of drug addicts. He’ll get the last hoorah when he works out a humane and constructive way of doing it.

Anybody who has commented on Scottish drug policy over the past 20 years is likely to be more sceptical than Pyrrho. But I can’t help feeling there is an innate hypocrisy in the establishment’s attitude to illegal drugs. Those who make drugs policy rarely experience its effects. But when they do, they can use their money and influence to work their way out of it.

This really hit home to me a few years ago during an interview with Mothers Against Drugs, a group set up in the Cranhill area of Glasgow following the death of 13-year-old Allan Harper, the youngest heroin addict to die in Britain. Sitting in a neat living room on an estate where the detritus in the local swing park wasn’t sweetie wrappers but used condoms, burnt teaspoons, silver paper and needles, I heard mother after mother talk about how it felt to lie awake at night waiting for a knock on the door to tell you a child was slumped in a stairwell somewhere with a needle in his or her arm.

These women weren’t sophisticated or particularly articulate, but they were sincere. They were angry about the declassification of cannabis, about the confused messages being sent by those who would legalise drugs, and by the way celebrities embracing the drug culture were tolerated.

“See these politicians. They do my head in,” one of them said. “They’re not living in Cranhill. They’re sitting in safe, warm houses. Their weans can go to university. They can socialise at their parties with their cannabis and their drink. They’re not worried sick that the next step will be heroin.”

Far from being the relatively benign substance of the liberal middle classes, cannabis in Cranhill was a precursor to serious addiction. Dealers pushed it to children and then cut their supplies for three or four weeks before offering them something stronger, initially for free. Some 85% of the heroin addicts these women knew had been hooked this way.

Of course, there are families from all walks of life who have been devastated by drug misuse and that is not to disparage their pain. But I cannot see how educators can hope to get any kind of consistent message through to children when large swathes of society are happy to condone drug misuse. When Kate Moss was caught snorting cocaine, it was simply taken as read that cocaine and ecstasy abuse is ubiquitous among the Metropolitan elite. It has done her career no harm. An idol to thousands of young girls, Moss is in more demand now than ever.

For the David Cameron generation, dabbling in drugs is as much a part of puberty as learning to shave. If it all gets out of hand they can be fast-tracked into the Priory or a five-star clinic in Arizona. There is no stigma attached to addiction if it is wrapped in designer clothes or snorted through £100 notes, only if it is dressed in a baseball cap and swigging a bottle of Buckfast.

Until the authorities start treating all drug abuse equally seriously and all addicts the same, we have no hope of even formulating, let alone implementing, effective policy. It’s not rocket science — any five-year-old could tell you that.

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