Catalonia has some 400 cannabis clubs. CONSUELO BAUTISTA

Some 20 years ago, a Spanish official in favor of lifting the ban on drugs such as marijuana mentioned at a UN meeting that there "might be a more humane option" in the fight against trafficking. She was immediately taken aside by a senior diplomat, who told her in no uncertain terms: "Don't say things like that round here, not even in the washroom." Today, the same official says that internal documents are now circulating within the UN that openly admit to the failure of prohibition.

The taboo is finally being broken down: it is no longer considered madness to suggest a different approach to controlling the trade in illegal substances (above all cannabis) to that taken over the last half century following the 1961 Single Convention on Narcotic Drugs at the UN headquarters in New York. What's more, the profile of those proposing a sea change has altered. The habitual user, typically left leaning, who a few years ago would have attended demonstrations calling for the legalization of cannabis, has now been joined by a pantheon that includes novelists Mario Vargas Llosa and Gabriel García Márquez, (whose respective countries, Peru and Colombia, have been torn apart by drug wars), along with former UN chief Kofi Annan, several former heads of state from around the world, the current presidents of a number of Latin American nations, and even former NATO boss and Spanish politician Javier Solana.

Pointing out that the benefits of prohibition have not outweighed its costs no longer surprises anybody. "The most important thing here is that the debate has been legalized," says Xabier Arana, a researcher at the Basque Institute of Criminology. "Before, the prohibitionists would simply tell you that this hypothesis was not valid; at least now they are asking how a different approach might work."

Portugal’s successful experiment ANTONIO JIMÉNEZ BARCA During the 1980s, heroin consumption in Portugal and the related increase in AIDS cases were among the highest in Europe. Repressive policies to deal with the problem were not working, and so in 1998, a committee of government-appointed experts recommended decriminalizing use. The law was approved in 2001, and is still in place. Broadly speaking, the law works like this: drug consumption is prohibited, but it is a civil, not a criminal, offense. So if the police find drugs on somebody, whether those drugs are cannabis or heroin, they are taken to the station house. If they are carrying over a certain amount, they will be charged with dealing. If the amount is smaller, they are not charged, but instead must appear before a panel made up of a social worker, a lawyer and a psychologist. The panel will assess the degree of addiction, advising treatment if it considers this necessary. If somebody is detained several times, they can be fined or given community work, or banned from entering certain establishments where drugs are known to be used or suspected of being bought and sold. But the matter remains out of the criminal courts. João Castel-Branco Goulão, the head of the Portuguese Health Ministry's drug-dependence treatment service, says that the aim is to avoid stigmatizing users, giving them time and the opportunity to undergo rehabilitation. "We aim to pursue the illness, not the ill. The Portuguese state is still opposed to the use of illegal drugs. Which is why consumption remains banned. But we are not against drug addicts, which is why they do not enter the criminal justice system. The idea is that once they have undergone rehabilitation they can return to a normal life, because they will not have a police record, which makes it easier to get a job and find somewhere to live." Castel-Branco Goulão says that the statistics support Portugal's approach: "In 1997, there were around 100,000 drug addicts that we could describe as 'tough cases,' most of them heroin users, around one percent of the population, which is a worryingly high figure. But that figure today has been halved. Consumption has developed along the lines of other countries, but there is better access to treatment," he says. Another important result of keeping drug users out of the courts is that more of them are prepared to seek help from the authorities to deal with their addiction, Castel-Branco Goulão explains. But Portugal is not necessarily heading in the direction of Uruguay, where, like alcohol, the government now regulates the production and consumption of marijuana. "Our law was approved almost 14 years ago. So we need to watch very carefully what happens in Uruguay. Nobody has any clear answers to this situation, but in the same way that other countries were watching to see what would happen here, we should now be watching to see what happens in Uruguay," says Castel-Branco Goulão.

Amsterdam, and the Dutch policy of allowing people to smoke marijuana in so-called coffee shops (although it has since banned non-nationals from doing so) is no longer a global exception, and a raft of countries, cities and regions are calling for the decriminalization of the possession of cannabis, or even allowing people to smoke it openly. What a few years ago would have been a utopian idea, that of a country legalizing marijuana, is now a reality in Uruguay, where the government is to take over the production, distribution and sale of marijuana. The experiment is being watched closely around the world, particularly by Uruguay's neighbors in Latin America, where the war on drugs kills thousands of people every year.

The example of the United States perhaps best illustrates the way that thinking has begun to shift toward other options. Back in 1971, President Richard Nixon declared a "world war against drugs." There are now 21 states that permit the consumption of marijuana for medicinal purposes, and in some, such as California, the line between therapeutic consumption and recreational use is ever more blurred. Colorado and Washington have gone further: the former now permits people to grow up to six plants at home, and to legally sell up to 28 grams of marijuana for recreational use. Washington state will follow suit sometime this year. The latest nationwide Gallup Poll in the United States on the legalization of cannabis showed that 58 percent of those surveyed were in favor of the measure. The first time the question was included in the survey, in 1961, just 12 percent agreed with legalization. This change of mind has come about over a short period of time: a third of those who now support legalization were against it just three years ago.

Some US pundits say the avalanche of new laws permitting cannabis use, which is consumed by at least 162 million people around the world, reflects economic recovery. Sales of medicinal-use marijuana topped 110 billion euros in 2013, and it is estimated that the figure will reach 438 billion euros by 2018. There is already an entire university, in Oakland, California, dedicated entirely to studying the (legal) money-making opportunities related to cannabis, while a number of leading figures from the business community that until now had nothing to do with the drug, are now saying it has a big future. The swing came after US Attorney General Eric Holder said that the government would not be taking legal action against Colorado and Washington, despite the fact that at the federal level, cannabis remains an illegal substance.

"This is a huge market in search of a brand," said James Shively, a former Microsoft board member, at last June's presentation of his project to create the "Starbucks" of marijuana, into which he is going to personally invest an initial 7.3 million euros. Accompanied by Vicente Fox, the former president of Mexico, who supports the project, Shively said that marijuana was enjoying a "historic moment." Shively said US federal laws making the use, sale or possession of marijuana illegal were like the "crumbling" Berlin Wall shortly before its fall.

Uruguay's new laws could also be a business opportunity for the South American country. Canada's government, along with pharmaceutical companies in Israel and Chile, have begun talking to Montevideo about buying marijuana. The country could be transformed into a biotechnology hub and research center to study the medicinal use of marijuana.

Europe, which has traditionally taken a less harsh approach to drug use than the United States, is also showing signs of a new approach. In 2013, Switzerland decriminalized possession of cannabis for personal use; while the authorities in the Danish capital of Copenhagen want to take over the production and sale of marijuana; Berlin plans to introduce Dutch-style coffee shops in its Kreutzberg district.

But Spain, where 80 percent of drugs prosecutions are cannabis-related, is going against the global trend. The government has just announced measures to close down private smoking clubs, ban home-grown plants, and to introduce heavy fines. It also intends to end the practice of waiving fines for users who agree to undergo treatment. Is this a futile attempt to turn back the clock?

"It is easier for a 15-year-old to buy cannabis or an ecstasy pill than it is to get a bottle of vodka," says Araceli Manjón-Cabeza, a judge and former head of Spain's drugs program, who used to believe in prohibition but is now a firm proponent of legalization. "When substances are regulated it is easier to control access," she says.

World leaders are now awaiting a special meeting of the General Assembly of the United Nations in 2016 that will address the global drugs question, and is expected to announce a change in policy. "Anything could happen," says Manjón-Cabeza, adding, with a note of caution: "Bearing in mind the changes of the last couple of years, it's hard to make predictions."