In just a couple of days, President Obama will fly to Cartagena, Colombia, to attend this weekend's Organization of American States (OAS) Sixth Summit of the Americas. He and the US delegation are going to get an earful of criticism of US drug policies from Latin American leaders, and that makes it an historic occasion. For the first time, alternatives to drug prohibition are going to be on the agenda at a gathering of hemispheric heads of state.

It's been building for some time now. More than a decade ago, Uruguayan President Jorge Batlle became the first Latin American sitting head of state to call for a discussion of drug legalization. Former Mexican President Vicente Fox joined the call, albeit only briefly while still in office through some media quotes, much more frequently after leaving office in 2006. Honduran President Manuel Zelaya issued a similar call in 2008, but didn't move on it before being overthrown in a coup the following year.

Meanwhile, drug prohibition-related violence in Mexico exploded in the years since President Felipe Calderon called out the army after taking office in December 2006. As the savagery of the multi-sided Mexican drug wars intensified and the death toll accelerated, surpassing 50,000 by the end of last year, the call for another path grew ever louder and more insistent.

In 2009, a group of very prominent Latin American political leaders and public intellectuals led by former Brazilian President Henrique Cardoso, former Colombian President Cesar Gaviria, and former Mexican President Ernesto Zedillo formed the Latin American Commission on Drugs and Democracy, calling for a fundamental reexamination of drug policy in the hemisphere and a discussion of alternatives, including decriminalization and regulation of black markets. That was followed last year by the Global Commission on Drug Policy, which includes the Latin American ex-presidents, as well as former Switzerland President Ruth Dreiffus and other prominent citizens such as Richard Branson and former UN Secretary General Kofi Annan, echoing the Latin American Commission's call for reform.

As the commissions issued their reports, the violence in Mexico not only worsened, it spread south into Central America, where governments were weaker, poverty more endemic, and violent street gangs already well-entrenched. Guatemala, Honduras, and El Salvador, in particular, saw homicide rates soar in recent years, well beyond Mexico's, as the Mexican cartels moved into the region, a key transit point on the cocaine trail from South America to the insatiable consumers of the north.

Colombian President Juan Manuel Santos, the secretary of defense under his predecessor, Alvaro Uribe, and a man who knows well just what a sustained war on drugs can and cannot achieve, has been among the latest to pick up the torch of drug reform. Santos has made repeated statements in favor of putting alternatives to prohibition on the table, although he has been careful to say Colombia doesn't want to go it alone, and now he has been joined by another unlikely reformer, Guatemalan President Otto Perez Molina, a rightist former general who campaigned on a tough on crime agenda.

It is Perez Molina who has been most active in recent weeks, calling for a Central American summit last month to discuss alternatives to drug prohibition ranging from decriminalization to regulated drug transit corridors to charging the US a "tax" on seized drugs. That summit saw two of his regional colleagues attend, Costa Rican President Laura Chinchilla and Panamian President Ricardo Martinelli, but no consensus was achieved, no declaration was issued, and three other regional leaders declined to show up. But that summit, too, was a first -- the first time Latin American leaders met specifically to discuss regional drug law reform.

All of this has not gone unnoticed by policymakers in Washington. Vice-President Biden, Homeland Security Secretary Napolitano, State Department functionaries and US military brass have all been flying south this year, reluctantly conceding that drug legalization may be a legitimate topic of debate, but that the US is having none of it.

"It's worth discussing," Biden told reporters in Mexico City last month. "But there's no possibility the Obama-Biden administration will change its policy on legalization. There are more problems with legalization than non-legalization."

But along with discussing an end to prohibition, the Latin Americans have also offered up proposals between the polar opposites of prohibition and legalization. Options discussed have included decriminalization of drug possession and marijuana legalization to different approaches to combating the drug trade to maintaining addicts with a regulated drug supply. In Colombia, Santos has sponsored legislation to decriminalize possession of "personal dose" quantities of drugs, restoring a policy mandated by the country's Constitutional Court but undone by a constitutional amendment under President Uribe.

And it's not just Latin American political leaders. The calls for change at the top are reflected in a civil society movement for drug reform that has been quietly percolating for years. In fact, an international, but mainly Latin American, group of non-governmental organizations this week issued an Open Letter to the Presidents of the Americas calling for decriminalizing drug use and possession, alternatives to incarceration for non-serious drug offenses, a regulated market for marijuana, a public health approach to problematic drug use, alternative development, respect for traditional uses, and a more focused war on organized crime that is less broadly repressive than current models. In Mexico, a social movement led by poet Javier Sicilia, whose son fell victim to cartel violence, has called for an end to the violence and pressed Preident Calderon on drug reform.

After decades of US-imposed drug war, from US military operations in Bolivia in the 1980s to the multi-billion dollar Plan Colombia, with its counterinsurgency and aerial herbicide spraying, to the blood-stained Mexican border towns and the drug gang-ridden slums of Rio de Janeiro, Latin America is growing increasingly ready to strike out on a different path.

That's what awaits President Obama and the US delegation in Cartagena. The most vibrant discussions may well take place in hallways or behind closed doors, but the US is now faced with yawning cracks in its decades-long drug war consensus.

"It's very clear that we may be reaching a point of critical mass where a sufficient number of people are raising the questions of why not dialog on this issue, why not discuss it, why peremptorily dismiss it, why does the president laugh when the subject of drugs is brought up, is he so archly political that it becomes a sort of diabolical act to seriously discuss it, why isn't some new direction being ventured forth?" said Larry Birns, executive director of the Council on Hemispheric Affairs.

"It seems the public is approaching the point where it has become credible to say quite frankly that the drug war hasn't worked. The real menace to society is not so much legalization but the failure to confront the hard fact that after decades of effort and hundreds of billions of dollars, a successful prohibition strategy has not been created, nor is there any likelihood of it being created," he said.

"This is the first major gathering of heads of state at which alternatives to prohibitionist drug control policies, including decriminalization and legal regulation of currently illegal drugs, will be on the agenda," said Ethan Nadelmann, head of the Drug Policy Alliance. "Arguments that were articulated just five years ago primarily by intellectuals and activists, and three years ago by former presidents, are now being advanced, with growing sophistication and nuance, by current presidents. There is now, for the first time, a critical mass of support in the Americas that ensures that this burgeoning debate will no longer be suppressed."

"A lot of countries don't want to do the US's dirty work anymore -- enforcing the prohibitionist policies that are unenforceable and hypocritical," said Laura Carlson, director for Latin America rights and security in the Americas program at the Center for International Policy. "Everybody knows that it's impossible to wipe out the illicit drug business without making it legal, and most people know that the efforts aimed at ostensibly doing that are not 100% honest and certainly not effective. Many Latin American countries don't want the degree of US intervention in their national security that the drug war entails either," she noted.

"Having said that, the US government is determined to put down any talk of alternatives and particularly alternatives that begin with regulation rather than prohibition. The recent visits of Napolitano, Biden, [US State Department Assistant Secretary for the Bureau of International Narcotics and Law Enforcement Affairs William] Brownfield and the military leaders all carried that message," the Mexico City-based analyst continued. "Small and dependent countries -- El Salvador is the example here, after reversing its position on legalization -- are afraid to stand up to the US on this, and progressive countries don't seem to want to get involved, both because they find the issue a political hot potato and because they are focusing efforts on strengthening alternative organizations to the OAS."

"I think the US strategy of Brownfield and the State Department will be to say that legalization was brought up and rejected by the Latin American leaders," offered Sanho Tree, director of the Drug Policy Project at the Institute for Policy Studies. "They will use dichotomous rhetoric, they will try to maneuver the discussion into either prohibition or heroin in vending machines, but this is about the whole spectrum of regulatory possibilities. That's what we need to be talking about instead of that false dichotomy."

Still, to even deign to discuss policy alternatives to prohibition is a notable step forward for the US, even if it is only to dismiss them, Nadelmann argued.

"The shift in the public posture of the US government -- from rejecting any discussion of legalization to acknowledging that 'it is a legitimate subject of debate' -- is significant, notwithstanding the clear caveat by the Obama administration that it remains firmly opposed to the notion," he noted. "That said, it is safe to assume that the US government will do all it can to suppress, ignore, distort and otherwise derail the emerging dialog.  US officials are handicapped, however, by the remarkable failure of government agencies over the past thirty years to contemplate, much less evaluate, alternative drug control strategies. They also must contend with the fact that the United States has rapidly emerged -- at the level of civil society, public opinion and state government -- as a global leader in reform of marijuana policies."

The discussion on drug policy at Cartagena isn't taking place in a vacuum, and there is at least one other issue where the US finds itself at odds with its host and most of the region: Cuba. The US has once again insisted that Cuba not be allowed to attend the summit, and President Santos reluctantly acceded, but the whole affair leaves a sour taste in the mouth of Latin Americans. Ecuadorian President Correa is not coming because of the snub, and the issue only plays into hemispheric discontent with Washington's war on drugs.

"The US won the day in persuading Santos not to invite Cuba," said Birns, "but the political cost of that action is high, and the whole drug issue is twinned to it, not because Castro has an enlightened position on drugs, but because of anti-Americanism in the region. This means Cartagena is the city where a lethal blow against the status quo will be achieved."

"The United States is not going to listen," said Birns, "but this era of non-discussion of drug legalization and refusal to countenance the possibility of dialog on the issue may be coming to an end. More and more people who aren't known as drug reform crusaders are coming forth and saying it's not working, that we need another approach, and that's probably decriminalization and legalization. We're very much closer to liberation on this issue than we've ever been before."

"Liberation" may now be within sight, but diplomatic dissent is not yet close to being translated into paradigmatic policy shifts. Whatever discussion does take place in Cartagena this weekend, don't expect any official breakthroughs or even declarations, said Carlson.

"I am not optimistic about there being any formal commitment, or perhaps even mention, of legalization per se," she said. "The implementation group for the Sixth Summit is already working on the final declaration and it contains a section on 'Citizen Security and Transnational Organized Crime.' I think that as far as it will go is to state that transnational organized crime is a growing problem and that the nations of the Americas agree to work together, blah, blah, blah," she predicted.

"The United States will reiterate its 'shared responsibility' and commitment, but will not mention the need to change a failed model," Carlson said. "There will be more rhetorical emphasis on social programs for 'resilient communities' and especially on police and judicial reform, although the former will not be reflected in what are largely military and police budgets. I think the best we can hope would be a mandate for a policy review and a commitment to continue to discuss alternatives. The specific proposals to legalize transit, to create a regional court for organized crime cases and US payment for interdictions will not likely be resolved."

"This is a long process, not an immediate objective," said Tree. "In Central America, it's going to take a year or two of thoughtful -- not sensational -- media coverage. When people see anarchy, they want order. With a more thoughtful dialog, we can begin to get traction."

"It is too soon to predict that this Summit of the Americas represents any sort of tipping point in global or even regional drug control policy," Nadelmann summed up. "But the odds are good that this gathering will one day be viewed as a pivotal moment in the transformation from the failed global drug prohibition regime of the twentieth century to a new 21st century global drug control regime better grounded in science, health, fiscal prudence and human rights."

We'll see what happens this weekend, but at the very least, the taboo on serious discussion of reforming the drug prohibition regime at the highest levels has been shattered. Look for a report on the summit itself next week.

Ricardo Soberon, the reformist head of DEVIDA, the Peruvian drug agency, has been fired and replaced, the Peruvian government announced Tuesday. Soberon made waves last August when he implemented a temporary ban on forced eradication of coca plants, taking the US Embassy by surprise, but that was soon reversed on the orders of his boss, Interior Minister Oscar Valdes.

Relations between Soberon and Valdes never warmed, and he "resigned" on Tuesday after just five months in office. Soberon also found himself increasingly at odds with President Ollanta Humala, who had campaigned on a pledge to not aggressively pursue eradication, but who has shifted to the right on this and other issues since taking power.

Soberon had taken that same message to coca growers, with whom he had forged relationships after years of work in the field. His departure could mean an uptick in conflict in the already contentious relationship between coca grower unions and the government.

"Soberon's exit was a matter of time," Peruvian drug policy expert Jaime Antezana told the Washington Post. "There was no chance that Oscar Valdes would keep him in the job."

Soberon had been working on a five-year national drug strategy that would have called for vigorous pursuit of cocaine traffickers and money launderers and interdiction of incoming precursor chemicals and outgoing cocaine, but de-emphasized punishing the peasants who grow coca outside the government coca monopoly, ENACO. That strategy was never approved.

Peru is now arguably the world's largest producer of cocaine, having surpassed Colombia despite the latter country's having more acreage of coca planted, according to US officials. Peru's coca fields are higher-yielding because they are more mature, and the country had the potential to produce 325 metric tons of cocaine last year, compared to 270 tons in Colombia.

Peru eradicated about 15% of the crop last year, but at the political price of alienating thousands of coca growing farm families. Now, it appears ready to deepen that divide.

Using pathogenic fungi to eradicate coca, opium, or other illicit drug crops is too risky because there is not enough data about how to control them and what effect they could have on people and the environment, according to a panel of scientists commissioned to study the subject by the Office of National Drug Control Policy (ONDCP -- the drug czar's office).

The finding came in a report, Feasibility of Using Mycoherbicides for Controlling Illicit Drug Crops, which was released November 30 by a panel of scientists convened by the National Research Council (NRC). ONDCP requested the report after it was required do to so by Congress in its 2006 budget authorization bill.

Mycoherbicides are killer fungi that can be targeted at specific plants and reproduce themselves, staying in the soil for years. Hard-line drug control advocates have urged their use against coca in Colombia and opium in Afghanistan, seeing them as a potential "magic bullet" that could eliminate drug problems at the source. But Colombia rejected the use of mycoherbicides in 2002 and the Afghan government has strongly signaled that it is not interested in using them there.

The NRC scientists found that the evidence base to support using mycoherbicides was scanty. "Questions about the degree of control that could be achieved with such mycoherbicides, as well as uncertainties about their potential effects on non-target plants, microorganisms, animals, humans, and the environment must be addressed before considering deployment," they said.

The panel did not reject outright the use of mycoherbicides; instead, it recommended "research to study several candidate strains of each fungus in order to identify the most efficacious under a broad array of environmental conditions." But it warned that "conducting the research does not guarantee that a feasible mycoherbicide product will result, countermeasures can be developed against mycoherbicides, and there are unavoidable risks from releasing substantial numbers of living organisms into an ecosystem."

The use of mycoherbicides would require meeting multiple domestic regulatory requirements, as well as possible additional regulations and agreements before being used on drug crops in foreign countries, the report noted. That might also prove problematic because "approval to conduct tests in countries where mycoherbicides might be used has been difficult or impossible to obtain in the past."

Congressional and bureaucratic drug warriors are going to have to look elsewhere for their "magic bullet" to win the war on drugs -- unless they're in the mood to appropriate more funds for more research that may or may not come up with a workable mycoherbicide. Then all they would have to do is sell the idea to the government of the country they want to spray it on.

Newly installed Peruvian President Ollanta Humala is facing the first serious challenge to his authority as coca farmer unions have gone on strike to protest the resumption of coca plant eradication. Just last month, in a nod to growers whom he had promised he would halt involuntary eradication, Humala's government announced a temporary halt to eradication in the Upper Huallaga River Valley, but now eradication is again underway, and the coca farmer unions are up in arms.

Earlier this week, strikers erected roadblocks on a major regional highway, and two people had been injured and seven arrested by the time Humala declared a 60-day state of emergency in the Ucayali region Tuesday night. Coca grower unions are threatening an "indefinite national strike" within two weeks if forced eradication isn't ended.

Coca has been grown in Peru for thousands of years and is an intrinsic part of Andean life. Although international anti-drug treaties consider it a controlled substance, tens of thousands of Peruvian farmers grow it legally under license from ENACO, the Peruvian state coca monopoly, which then sells the product for traditional, nutritional and industrial uses.

But tens of thousands of other coca farmers are not registered with ENACO, and their product often ends up being processed into cocaine for the insatiable North American, European, and Brazilian markets. According to the UN Office on Drugs and Crime, Peru has now surpassed Colombia as the world's largest coca leaf producer with 61,000 hectares planted, up 2% from last year.

"Eighty percent of the population here are farmers who want the government to redirect its eradication efforts," Jaime García, deputy mayor of the town of Padre Abad in Ucayali, told local radio in remarks reported by the Financial Times.

The same newspaper reported that Nelson Torres, head of the Ucayali chamber of commerce estimated the growers' road blockade was costing $3.6 million a day. He was dismissive of the Humala government's early steps to contain the conflict. "It's the same policy as the previous government," he told local radio. "You have to have to go on strike or create stoppages just to sit down and talk."

Perhaps Ricaro Soberon, the head of the Peruvian anti-drug agency DEVIDA, is belatedly getting that message. He finally met with coca growers on Monday, but not before he told reporters in Lima last week that the Humala government will implement a "sustainable" eradication program that replaces coca with alternative crops. The country will also increase anti-drug spending 20% next year, step up interdiction efforts, and institute tighter controls on chemicals used to process coca into cocaine, Soberon said.

"Crop reduction must be definitive, which means replacing coca with an economically viable alternative," said Soberon. "This problem is well beyond our ability to confront alone so we're worried about the trend of declining international aid."

Soberon, an attorney and drug policy expert who has been a critic of past eradication programs, has already faced calls for his resignation for being "soft" on coca, and the temporary halt to eradication also raised concerns in the US.

Now, though, Humala and Soberon have to balance their sympathy for coca farmers whose support they successfully sought during the election campaign, against demands from Washington and conservative factions inside Peru that they repress the crop. On Tuesday, the national coca growers' union CONPACCP (the National Confederation of Agricultural Producers of the Coca Valleys of Peru) issued a communique which announced that they would support an "indefinite national strike" against forced eradication within the next two weeks, even as they defended Soberon against attacks from the right.

"Agents of US interests, like [former interior minister] Fernando Rospigliosi have unleashed a campaign of destruction against one of the few specialists in drug traffic, Ricardo Soberon," CONPACCP noted. "They say that Soberon's closeness to the cocaleros is a defect, when in reality, it is a logical consequence of his work as an analyst who has studied deeply the problematic of coca leaf cultivation and who could, if they let him do his job, propose solutions that transcend mere repression and criminalization of the weakest link in the chain, which in this case is the growers, and not the grand narcos and the apparatus that they have created around the commercialization of cocaine hydrochloride and its derivatives."

While defending Soberon, CONPACCP called for further meetings in a bid to find a nonviolent solution to the conflict and demanded that Humala fulfill his campaign promise to end forced eradication. It also had specific criticisms of the eradication program in Ucayali.

"The forced eradication campaign is going on in zones next to the highway that are affiliated with the CONPACCP, small parcels where farmers deliver their coca to ENACO, while they are not eradicating the grand plantations of coca that can be found 12 miles from the highway," the union complained. "They are taking photos and making recordings of these roadside eradications and then showing them next to images of [cocaine production] maceration pits as if they were at the same site in order to deceive the population."

Authorities are not going after the big plantations because they have "corrupted" the eradication program to be "untouchable," CONPACCP continued. To not eradicate the big plantations connected to the drug trade while eradicating small plots of registered farmers results in "incoherent anti-drug policies of the government," the union argued.

The eradicators themselves are behaving lawlessly, CONPACCP complained. "Besides the unjust eradication, they are robbing the animals and goods of the population" and have "unjustly detained" seven peasant farmers "whose immediate liberation we demand."

CONPACCP is supporting the current "indefinite strike" in Ucayali and is giving the Humala government two weeks to show good faith before it calls for a national coca grower strike. Humala and Soberon are going to have their work cut out for them as they attempt to chart a course that pleases both the coca growers and Washington.