The so-called "War on Drugs" has cost the nation trillions of dollars and thousands of lives. 2012 Republican presidential candidate Ron Paul is absolutely correct in asserting that drug addiction should be treated as a disease and not as a crime. Unfortunately, he is the only remaining presidential candidate from either major political party who holds that view (Gary Johnson of the Libertarian Party also supports drug legalization).
Drug prohibition, like alcohol prohibition in the early 20th century, creates a black market for these products. The black market, as was the case with alcohol, creates the drug cartels, street gangs, and other semblance of the organized crime networks that facilitate the transfer of drugs. The cartels and street gangs are the source of much of the violence that occurs in urban neighborhoods today. Those who believe drug prohibition actually makes this country safer must wake up to the sobering reality. As long as the War on Drugs continues to persist, street gangs will continue to run the streets and taxpayers will continue to see their money wasted on this operation.