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.
In the US, Milton Friedman estimated that 10,000 people die every year as a result of drug dealers fighting over territory. 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.
Alcohol prohibition failed in the 1920s. People continued to consume alcohol, only it became 150 per cent stronger and was as easy to obtain for minors as adults.