All wars end. Eventually. Even the war on drugs – resilient for so long – is starting to show signs of exhaustion. It is 42 years since President Nixon introduced the Comprehensive Drug Abuse Prevention and Control Act of 1970. The act set out to reduce or eliminate the production, supply and consumption of illegal drugs. A year later, after a report revealed a heroin epidemic among US servicemen in Vietnam, the Nixon administration coined the phrase "war on drugs".