"The War on Drugs is a campaign of prohibition and foreign military aid and military intervention being undertaken by the United States government, with the assistance of participating countries, intended to both define and reduce the illegal drug trade. This initiative includes a set of drug policies of the United States that are intended to discourage the production, distribution, and consumption of illegalpsychoactive drugs. The term "War on Drugs" was first used by President Richard Nixon in 1971....

"In June 2011, the Global Commission on Drug Policy released a critical report on the War on Drugs, declaring 'The global war on drugs has failed, with devastating consequences for individuals and societies around the world. Fifty years after the initiation of the UN Single Convention on Narcotic Drugs, and years after President Nixon launched the US government’s war on drugs, fundamental reforms in national and global drug control policies are urgently needed.' The report was immediately criticized by organizations that oppose a general legalization of drugs.

"A 2008 study by Harvard economist Jeffrey A. Miron has estimated that legalizing drugs would inject $76.8 billion a year into the U.S. economy — $44.1 billion from law enforcement savings, and at least $32.7 billion in tax revenue ($6.7 billion from marijuana, $22.5 billion from cocaine and heroin, remainder from other drugs).
http://en.wikipedia.org/wiki/War_on_Drugs#Costs_to_taxpayers


The war on drugs costs American taxpayers an estimated $40 billion per year.
http://www.skeptive.com/disputes/1264