When I open my email these days, I find it flooded with various commercial offers. Especially around cannabis products. Now is the right moment, I'm informed, to invest in cannabis. It's getting legal everywhere! It's a profitable product - and, besides, it helps with a range of illnesses "including chronic pain, anxiety, arthritis, diabetes, PTSD, strokes, cardiovascular disease, and even cancer".

Justin Trudeau's Canada has legalised it and Canadians can now buy marijuana with names like Girl Scout Cookies, Green Crack and Suicide Girl (eh?) from government-licensed companies. And it's been legalised in Colorado and some other American states for a while now.

It's hard to know what to think of this trend. Many people support marijuana and cannabis for medical use (CNN reports that seven in 10 Americans approve of athletes using it to alleviate pain), and it seems a worthy application of the drug. People with terminal illness are pumped with opium to relieve pain and distress, and why not? Yet, when my sister was dying in New York, I had to sign a waiver saying we would not sue the hospice for making her a dope addict - for absurd legal reasons.

But when it comes to cannabis, I also know it can be so harmful. The Middle East specialist Patrick Cockburn - who grew up in Youghal - has written with his son, Henry, a heart-wrenching book called Henry's Demons: Living with Schizophrenia, which describes how Henry, as a teenager, descended into a hell of schizophrenia most likely triggered, they believe, by cannabis use.

Time for me to have a renewed conversation with Grainne Kenny, a dynamo of a woman - 80 this year but utterly undiminished in energy - who, as a long-time president of Eurad, the European non-profit network against drugs, and now honorary president, has campaigned against drugs in Ireland since 1979. Isn't there an argument for legalising cannabis for the relief of pain?

Grainne thinks that a lot of the campaigning for medical use is often a ploy to normalise use for recreational reasons. The adverts that are coming into my mailbox about the wonders of cannabis are more about Big Pharma taking over from Big Tobacco than about compassion for the afflicted. And, Grainne says, you'd be asking someone with an illness to smoke a joint, because that's the most practical way of getting the cannabis inside you. Since health advisors want to halt smoking, it's hardly a sensible course.

What about inhaling it through cannabis oil, which is now much promoted as a healing property? Some cancer survivors claim to have been helped by it. Grainne is not convinced that any cannabis-based product is without side effects, and cannabidiol can be much stronger than ordinary pot, too.

Moreover, cannabis can cause cancer - the British Lung Foundation found that tar from joints contains 50% more carcinogens than cigarettes made from tobacco alone - rather than cure it. People with a chronic illness who need a relaxant "would probably be better off with a gin and tonic", Grainne says. Alcohol, though a serious drug, is not a narcotic or a psychotropic. And we have been acculturated to alcohol for over 5,000 years.

But what about the trend, in North America, to be more accepting now of cannabis-based products? In this, Grainne sees the influence of the financier George Soros (backed, on this side of the Atlantic, by Richard Branson), who has donated millions to drug liberalisation.

Besides, some of the outcomes of legalisation are already dubious. In Colorado, where you can buy cannabis legally, the dealers have moved in and are trading it elsewhere - and criminally. For similar reasons, the Dutch have pulled back from their formerly easy-going approach to soft drugs: every dopehead in Europe was heading for Amsterdam, and they didn't like the overall effect on their cities.

The state of Utah, which was preparing to legalise cannabis, is pausing to reflect, and New Hampshire - in the liberal northeast - has voted against. Britain has toughened legislation against cannabis possession and the health authority NICE has ruled out funding the cannabis-based medication Sativex, although it is used in Wales to control muscle spasms (and, recently, an 11-year-old epileptic boy, Billy Caldwell, in Northern Ireland was given prescriptive cannabis oil).

Sweden, which Grainne regards as the gold standard, has held firm and remains solidly opposed to any liberalisation of drugs.

Many commentators believe that the 'war on drugs' is a failure - achieving little except enriching criminals. But there's no easy remedy to legalising it. "Who's going to sell this stuff? Distribute it? Tax it?" Tax it too highly, and there will be a parallel black market anyway. Tax it too low and the State is irresponsibly encouraging young people to take up the drug habit.

But won't people always seek some kind of drug? Because human beings cannot bear too much reality. Grainne concedes this may be so. Yet you can do a lot with drug education - not by lecturing young people but by engaging them. Teenage girls, she says, are so responsive: they worry about their friends. Lads are more likely to guffaw and show off.

Surely that, at least, is something we can all agree on - that serious, engaged education around the drug question is a vital backdrop to the increased clamour for liberalisation?

Belfast Telegraph