There's no subject in our culture where the conversation is dominated by myths and misconceptions so much as drugs. We are frightened to talk about it. We are tempted to fall back on stock-phrases and mental spasms -- Just Say No, and all its more modern twists.

I have always been sympathetic to more compassionate drug policies, and I thought of myself as pretty enlightened. But when I spent over three years researching my book Chasing The Scream: The First and Last Days of the War on Drugs, I was startled to discover -- time and again -- that I too had fallen for a shelf-load of myths.

Here are seven facts I learned along the way that startled me -- and I think force us to think differently about the drug war we have been waging now for one hundred and one years.

Fact One: 85 percent to 90 percent of people who use even heroin, crack or meth don't become addicted.

If you go into a crowded bar tonight and look around you, you might see some alcoholics (who need our love and support) -- but we all know they're a small minority.

But this isn't true of most other drugs, is it? We all know that most people who use heroin or crack or meth become addicts.

This question has been carefully studied by leading social scientists -- and it turns out this belief is a myth. As I learned from Professor Carl Hart at Columbia University, it turns out 85-90 percent of people who use any drug do not become addicted.

Even the UN Office of Drug Control -- the main drug war body in the world -- admitted that 90 percent of all currently banned drug use doesn't harm the user -- although they've pulled the link from their site.

Fact Two: Portugal decriminalized all drugs -- and injecting drug use fell by 50 percent.

By the year 2000, Portugal had a massive drug crisis, with 1 percent of the population addicted to heroin. They set up a panel of scientists to look at the evidence. They came back and said -- decriminalize all drugs, and transfer all the money they used to spend on making addicts' lives worse, to making their lives better.

They set up a huge program of job creation for addicts, and extensive wrap-around care.

The result? Injecting drug use fell by 50 percent; overdose deaths fell significantly; and very few people in Portugal want to go back.

Fact Three: Switzerland legalized heroin for addicts over a decade ago. Nobody has ever died on an overdose there on legal heroin.

Switzerland also had a huge heroin crisis. Under a visionary president -- Ruth Dreifus -- they decided to try an experiment. If you are a heroin addict, you are assigned to a clinic, and you are given your heroin there, for free, where you use it supervised by a doctor or nurse. You are given support to turn your life around, and find a job, and housing.

The result? Nobody has died of an overdose on legal heroin -- literally nobody. Street crime fell significantly. The heroin epidemic ended. Most legal heroin users choose to reduce their dose and come off the program over time, because as they find work, and no longer feel stigmatized, they want to be present in their lives again.



"When it comes to drugs, we can continue to live in a fantasy-world if we want -- and we will keep getting the results we've got."



Fact Four: A Harvard Professor calculates the murder rate would fall by at least 25 percent after legalization.

When you ban drugs, they don't vanish. They are transferred from legal businesses to criminals. If you try to steal from a legal business, they can go to the police. If you try to steal from a criminal gang, they can't go to the police. Illegal businesses can only survive through violence and the threat of violence. As the writer Charles Bowden said, the war on drugs creates a war for drugs. The Nobel Prize winning economist Milton Friedman calculated this dynamic kills 10,000 people every year in the US.

Professor Jeffrey Miron has carefully studied the very significant fall in the murder rate following the end of alcohol prohibition. Using these figures, he has calculated that when the war on drugs ends, there will be a fall in the murder rate of between 25 percent and 75 percent as the war for drugs ends. Under prohibition, everyone feared Al Capone; nobody fears the head of Corr's.

Fact Five: Kids find it much easier to get hold of illegal drugs than legal drugs.

In a major survey, American kids said it was easier to get hold of cannabis than to get hold of beer or cigarettes. In fact, kids were more than twice as likely to say they could easily get cannabis than beer.

Why? Drug dealers don't check ID. A legal, licensed trade has a lot to lose if they sell to teens. An illegal trade has nothing to lose -- a 13-year-old is as good a customer as a 35-year-old. Most legalization campaigners see it as a way to restrict access from younger people, who we all agree need to be protected.

Fact Six: Addiction is not caused primarily by the drug you take; it's caused by distress.

If 85-90 percent of people who use drugs don't become addicted, what's happening with the 10-15 percent who do? We now know it's not primarily the drug. Think about gambling addicts. They're just as addicted as any alcoholic or heroin addict you'll meet -- but nobody thinks you inject a roulette wheel, or drink a pack of cards.

So what does cause addiction? This short animation explains:

Fact Seven: When people see drug reform in practice, few want to go back.

When people first hear about the idea of decriminalizing or legalizing drugs, they understandably think it sounds really risky. But everywhere it has been tried, support went up significantly.

For example, a year after marijuana was put on sale in licensed stores in Colorado, 58 percent supported the legalization, and only 38 percent opposed it. When Switzerland -- a really conservative country -- was asked to vote on whether to reverse the legalization of heroin for addicts, 70 percent of citizens voted to keep it legal -- because they had seen such remarkable results.

When it comes to drugs, we can continue to live in a fantasy-world if we want -- and we will keep getting the results we've got: a catastrophic heroin addiction epidemic across the U.S., spiraling overdose deaths, and teens finding it easier than ever to get the drug.

Or we can do something really original -- something few of us have done for a century now. We can start to look at the facts.

Johann Hari's New York Times best-selling book 'Chasing The Scream: The First and Last Days of the War on Drugs' is now available in paperback in the U.S. This article draws on the book, and these ideas have also appeared in other extracts. You can find out what people as varied as Elton John, Glenn Greenwald, Bill Maher, Dan Savage, B.J. Novak, Sam Harris and Naomi Klein have said about the book here.