If cannabis was legalized, it could be regulated  Many of the problems associated with cannabis use arise from the fact that it is illegal. Cannabis is the world’s most widely used illegal drug – 23% of Canadians admit to having smoked it and up to 7 million people in the UK are estimated to do so.  In 2009, the UN estimated that the market for illegal drugs was worth $320 billion. This market is run by criminals and is often blighted by violence. It has cost thousands of innocent lives, particularly in supplier countries such as Mexico and Afghanistan 1. In the US, Milton Friedman estimated that 10,000 people die every year as a result of drug dealers fighting over territory 2. Many of the victims are innocent people, caught in crossfire. By legalizing cannabis, the size of this market for illegal drugs would be significantly reduced and so, effectively, would the number of crimes and unnecessary deaths that come with it.  Another way of seeing the problems of prohibition is to look at the failed attempt at alcohol prohibition in the 1920s. People continued to consume alcohol, only it became 150 per cent stronger, was as easy to obtain for minors as for adults, and was sold by murderous gangsters like Al Capone 3.  Given all of the problems associated with prohibiting cannabis, it seems nonsensical to spend billions fighting a drugs war when instead governments could reduce crime and make money by selling cannabis in a regulated manner. They could spend some of the profit on treating people who did experience any harmful effects.  1.United Nations Office on Drugs and Crime, 2010,   2.Hari, 2009,