It’s a multi-billion dollar industry, driven by violent criminal gangs which has killed hundreds of thousands of people around the world, but is the so-called war on drugs working?Two world leaders do not think so. Former UN Secretary General Kofi Annan and former Brazilian president Fernando Henrique Cardoso say repressive approaches to containing drugs have failed.Both men are members of the Global Commission on Drug Policy – and they are calling for a new approach.In an newspaper opinion piece they wrote: “‘We called on governments to adopt more humane and effective ways of controlling and regulating drugs. We recommended that the criminalisation of drug use should be replaced by a public health approach.”We also appealed for countries to carefully test models of legal regulation as a means to undermine the power of organised crime, which thrives on illicit drug trafficking.”Those in favour of reform say the war on drugs is a colossal waste of government resources; regulation could instead yield billions in tax revenues; it would be a blow to organised crime and put drug dealers out of business, and it would cut street crime and violence related to drug trafficking.Those against legalising drugs say it would create a large black market; it would lead to yet more addicts and more crime; an increase in the use of soft drugs could see users graduate to harder drugs, and drugs could fall more easly into the hands of children.Drugs became a symbol of youthful rebellion and social upheaval in the 1960s, and in the summer of 1971 US President Richard Nixon first declared the so-called ‘war on drugs’.It is estimated to have cost more than one trillion dollars in the four decades since then, with the bill now running at 100 billion dollars a year.The UN estimates the drug market itself to be worth 1.3 trillion US dollars and growing, and generating profits of around 435 billion dollars a year.Latest UN figures show some 230 million people took illicit drugs in 2011, with estimates suggesting the number of drug-related deaths could be as high as a quarter of a million.Calls for the decriminalisation of drugs are growing stronger around the world.Portugal is seen as a pioneer. It decriminalised drug use twelve years ago, putting possession of a small amount of drugs on a par with illegal parking.Colorado and Washington in the US have legalised the recreational use of cannabis for those over 21.Chile, Ecuador and Colombia have ruled that the possession of drugs for personal use is no longer a crime.And Uruguay is considering a passing legislation which would see the government growing and selling marijuana, for as little as a dollar a gram.The Secretary General of Uruguay’s national Drug Board, Julio Calzada, said last week: “… starting with the passing of the law, and it being put into place, it will progressively capture more of some of the most important parts of the black market.”But the president of the Senate’s Health Commission, Alfredo Solari, countered: “It is not that it is a bad bill, it’s disastrous … we have a marijuana use problem at a certain level in some populations, so to minimize this problem we are going to compete with drug dealers.”So is it time for a fresh approach to the war on drugs based around legalisation and regulation?And can decriminalisation help reduce drug abuse and organised crime?To discuss this, Inside Story, with presenter Hazem Sika, is joined by guests: Sanho Tree, director of the Drug Policy Project which works to end the domestic and international war on drugs; Amanda Fielding, a drug policy reformer and founder of the Beckley Foundation, and Manuel Pinto Coelho, president of the Association for a Drug Free Portugal.