After 40 years of defeat and failure, America's "war on drugs" is being buried in the same fashion as it was born – amid bloodshed, confusion, corruption and scandal. US agents are being pulled from South America; Washington is putting its narcotics policy under review, and a newly confident region is no longer prepared to swallow its fatal Prohibition error. Indeed, after the expenditure of billions of dollars and the violent deaths of tens of thousands of people, a suitable epitaph for America's longest "war" may well be the plan, in Bolivia, for every family to be given the right to grow coca in its own backyard.

The outcome of this militarisation of drugs policy has been overwhelmingly negative. Military involvement in such an irregular war was not only unrealistic, but has also proved counterproductive. Every once in a while, a momentous triumph is announced in one or another country. But within a few years, the proliferation of front lines in the "war on drugs" reveals that such "success" was, at best, a pyrrhic victory. Meanwhile, democracy deteriorates, national insecurity spreads and human rights violations worsen.

Some anniversaries provide an occasion for celebration, others a time for reflection, still others a time for action. This June will mark forty years since President Nixon declared a "war on drugs," identifying drug abuse as "public enemy No. 1." As far as I know, no celebrations are planned. What's needed, indeed essential, are reflection -- and action.

Tomorrow marks the 79th anniversary of the beginning of the end of the U.S. prohibition on alcohol. On that day in 1932 John D. Rockefeller Jr., a vociferous advocate of temperance, called for the repeal of the 18th amendment in a letter published in the New York Times. Rockefeller had spent hundreds of thousands of dollars lobbying for the constitutional prohibition on alcohol. But his letter did more than admit the error of his investment. Because of his moral authority on the matter, it effectively ended the conservative taboo against admitting that the whole experiment had failed.

June 17 will mark forty years since President Richard Nixon, citing drug abuse as "public enemy No. 1," officially declared a "war on drugs." A trillion dollars and millions of ruined lives later, the war on drugs has proven to be a catastrophic failure.

Forty years after President Richard Nixon first declared a war on drugs, the officers who fought in it are calling for a truce. Former law enforcement officials gathered in the District of Columbia on Tuesday to announce their new report. It details the failures of the government's long battle against illegal drugs and denounces the Obama administration's current drug policies. "Since President Nixon declared 'war on drugs' four decades ago, this failed policy has led to millions of arrests, a trillion dollars spent and countless lives lost, yet drugs today are more available than ever," said Norm Stamper, former chief of police in Seattle and a speaker for legalization-advocacy group Law Enforcement Against Prohibition.

I recently returned from the desert city of Durango, Mexico, where forensic officials are still trying to identify some 240 corpses discovered this year in mass graves. More than 200 other bodies have been found in similar fosas across northern Mexico. All were victims, many of them innocent victims, of the drug-trafficking violence whose barbarity seems bottomless. But it's fueled in large part by the just as endless American appetite for illegal drugs – which itself is due in no small part to the fact that our anti-drug policies are so narrow-mindedly focused on battling supply instead of reducing demand.

The central statistic of Mexico's violent drug war – 40,000 gangland murders in the past five years – is repeated so often it almost fails to alarm us anymore. But what happened last Thursday, Aug. 25, in the northern business capital of Monterrey – 52 innocent people massacred after gangsters set fire to a casino, presumably in a drug-cartel extortion operation – left even President Felipe Calderón sounding distressed. So agitated, in fact, that drug-war analysts believe Calderón, in his speech the next day, signaled a change in philosophy and told the U.S. to think about legalizing drugs as a way of weakening vicious drug traffickers.

This contradicts one of the central tenets of the War on Drugs, which is that the psychopharmacological effects of drug use lead to criminal behavior. Most studies show that it's in fact the competition of an unregulated market that encourages the majority of violent crime. This concept was evidenced during the prohibition era in the 1920s, a time that coincided with an increase in crime, corruption, and contempt for law.

A leading distributor of crack cocaine in the 1980s would have preferred to have been a pot dealer, but was unable to find enough supply, he told The Huffington Post in an interview. "I wanted to sell pot. You couldn't get pot at a decent price -- I couldn't, nor the quantity," said Rick Ross, whose operation the Los Angeles Times dubbed "the Wal-Mart of crack dealing." Ross built one of the largest cocaine empires in the country. If the goal of U.S. drug policy is to lower demand by increasing price, Reagan's drug war did precisely the opposite, driving people away from pot and toward coke and crack.

“The drug war is weakening state institutions, infiltrating judicial systems and undermining rule of law,” all of which is bad for business, César Zamora, Nicaraguan businessman and vice president of the Association of American Chambers of Commerce in Latin America (AACCLA) told the Christian Science Monitor on February 16, 2012. The business community needs a complete economic analysis of the impact of drug policy to fully understand how American drug policy plays with their profits. Every investor should analyze how much the costs of drug policy shrink return on investment.

As we approach the 75th anniversary of marijuana prohibition in the United States on October 1, it is important to remember why marijuana was deemed illicit in the first place: "There are 100,000 total marijuana smokers in the US, and most are Negroes, Hispanics, Filipinos and entertainers. Their Satanic music, jazz and swing, result from marijuana usage. This marijuana causes white women to seek sexual relations with Negroes, entertainers and any others."- Harry Anslinger, first US Drug Czar.

"Exactly 80 years ago (in 1932), Colorado voters approved a ballot measure to appeal alcohol prohibition, and that came before it being repealed by the federal government," said Mason Tvert, co-director of the Yes on 64 campaign in Colorado. "And it was the individual states taking that type of action that ultimately resulted in the federal repeal (of Prohibition in 1933)." As happened with alcohol, so it is beginning to happen with marijuana. No matter what the outcome of the votes, the bugler is sounding retreat.

Last week was a momentous week, the beginning of the end, perhaps, of a national depravity – the "war on drugs". The voters of Colorado and Washington passed measures to legalise marijuana, amounting to local shifts, for the moment. So we shouldn't delude ourselves that the country will be transformed overnight, but the public thinking, the public spirit is being transformed. Finally, there is a growing realisation that this "war" has produced nothing but a legacy of failure. And who wants to be associated with failure?

A pro-marijuana group lost its legal battle when a federal appellate court ruled that marijuana would remain a Schedule I drug, defined as having no accepted medical value and a high potential for abuse. For years, the U.S. Drug Enforcement Administration and the National Institute for Drug Abuse have made it all but impossible to develop a robust body of research on the medical uses of marijuana. For a muscular agency that combats vicious drug criminals, the DEA acts like a terrified and obstinate toddler when it comes to basic science.

"Since declaring a war on drugs 40 years ago, the United States has spent more than a trillion dollars, arrested more than 45 million people, and racked up the highest incarceration rate in the world. Yet it remains laughably easy to obtain illegal drugs. So why do we continue down this same path? Why do we talk about the drug war as if it's a success? It's a charade." (See: The house I live in)

For four decades, libertarians, civil rights activists and drug treatment experts have stood outside of the political mainstream in arguing that the war on drugs was sending too many people to prison, wasting too much money, wrenching apart too many families -- and all for little or no public benefit. They were always in the minority. But a sign of a new reality emerged: for the first time in four decades of polling, the Pew Research Center found that more than half of Americans support legalizing marijuana.

A recent neuroscience study from Harvard Medical School claims to have discovered brain differences between people who smoke marijuana and people who do not. Such well-intentioned and seemingly objective science is actually a new chapter in a politicized and bigoted history of drug science in the United States. Different-looking brains tell us literally nothing about who these people are, what their lives are like, why they do or do not use marijuana, or what effects marijuana has had on them.

The Community Anti-Drug Coalition of America (CADCA), one of the largest anti-legalization organizations in the US has a curious sponsor: Purdue Pharma, the manufacturer of Oxy-Contin, the highly addictive painkiller that has been linked to thousands of overdose deaths nationwide. A familiar confederation of anti-pot interests have a financial stake in the status quo, including law enforcement agencies, pharmaceutical firms, and nonprofits funded by federal drug-prevention grants.

When the poster child for marijuana legalization is released from a U.S. prison later this week, he'll be re-entering a world where many of his ideas have taken root and in some places have sprouted right up. Marc Emery, Canada’s self-styled “Prince of Pot,” concludes a five-year sentence and will emerge into a lucrative marijuana landscape, where two U.S. states are now issuing recreational pot licences, medical growers are reaping profits and investors aren’t hedging on potential opportunities.