Thailand is on the verge of becoming the first country in Asia to legalize medical marijuana, with some advocates saying that nationwide legalization for recreational use might not be far behind.

It would be a landmark decision in a part of the world with some of the harshest drug laws on Earth. Thailand has the largest prison population in Southeast Asia, and the sixth-largest in the world. Inmates convicted of minor drug offenses make up the largest percentage of that population, and only 15 years ago, the country embarked on its own Duterte-style war on drugs that left hundreds of alleged drug dealers dead—including several weed dealers.

Yet, marijuana also has a long history in Thailand, according to experts like Kitty Chopaka, chief marketing officer for the pro-legalization group the Highland Network.

"Marijuana has always been a part of Thailand’s culture," Kitty told me. "For centuries, farmers would go out to the field, they would use Kratom, by chewing the Kratom leaves. Then they’d go home and smoke a bong. They’d smoke so that they could eat, relax, and then go to sleep. And then do the same thing all over again."

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But regionally, the battle to legalize certain drugs is moving in the other direction. In the Philippines, President Rodrigo Duterte's controversial crackdown has left more than 12,000 dead, most of them gunned down in a wave of extrajudicial killings that spiked once Duterte took office.

In Malaysia, a 29-year-old man was recently sentenced to death by hanging for selling cannabis oil for medical use on Facebook (although the case is now under review). And here in Indonesia, Duterte's brutal policies found a favorable audience. Indonesian police have killed around 100 suspected drug dealers, some of them caught with as little as 10 grams.

If you need an image of how things are different today picture this: In the past Thai police would burn marijuana, and other drugs, confiscated during busts in a massive bonfire each year. But last month, the police handed over 100 kilograms of marijuana to medical researchers to use in their studies instead. That's how much things have changed.

So, what's different about Thailand today? For Dr. Somyot Kittimunkong the answer is as clear as life and death. Somyot has been on the front lines of the fight to legalize medical marijuana in Thailand for years, arguing that there is evidence that the plant can be used to treat diseases like Parkinson's and certain kinds of cancer. And he's not alone.

"I've seen it a lot," Somyot, 53, told me. "I've seen doctors, a judge, and even high-level [government] ministers use cannabis oil to treat cancer. It's soldiers, police, and many, many more. I think in every occupation you can imagine, you'll find people using cannabis oil in Thailand as a treatment of their cancer."

Dr. Somyot Kittimunkong

We were sitting in a bright, sunny cafe outside Somyot's office at the Ministry of Public Health, a government institution located in an open, leafy campus on the outskirts of Bangkok. Mellow bossa nova was playing over the cafe's speakers as Somyot, a man who looks both scholarly and suave, explained how a dermatologist got so interested in marijuana in the first place.

"My younger brother," he said, then paused briefly, clearing the emotion from his throat. "My younger brother had thyroid cancer. I searched for a way to help him, but nothing helped, and then he died. After that, I found out that cannabis can kill cancer. At first, we only had lab results on how cannabis oil can kill cancer. But after that, I tried to find some more information that could help."

The science on this claim is still spotty. Yes, there have been hundreds of studies in legitimate, peer-reviewed medical journals that found that cannabinoids could be used to treat, among others, lung cancer, breast cancer, and possibly even brain cancer. But the vast majority of these studies have been conducted on lab-grown cancer cells, not actual human beings. Without a large clinical trial, there's no real way to determine whether or not cannabinoids, a chemical component of marijuana, can actually help or hurt cancer patients.

But, in countries like Thailand, these same clinical trials are often made impossible by laws prohibiting the growth and use of marijuana, explained Dr. Niyada Kiatying-Angsulee, the director of the Social Research Institute at Bangkok's Chulalongkorn University. Right now, university researchers need to receive special approval from the government to research banned substances. It's not impossible to be granted approval—right now Niyada and her team is researching medical uses for Kratom and Cannabis—but the process is hindering their work.

"Use in human subjects is not allowed. It is not possible to test in humans," Niyada said. "The penalties for breaking the law by growing or consuming cannabis are high. Physicians are not allowed to prescribe cannabis by the current law.

"Since we realized the medical benefits of cannabis, from literature reviews, laws from other countries, and as some pharmaceutical products that are already registered in some countries, we all advocate for using it in medical aspects."

The researchers found a sympathetic ear in Somyot, a doctor with a government institution who also wrote a book titled Marijuana is Medicine That Cures Cancer. The text helped raise his profile in Thailand and, behind-the-scenes, he was hard at work trying to convince the current military-run government to legalize medical marijuana. He thought, if cannabis oil even had the potential of working this well, why was it still illegal? He soon brought together a team to lobby the junta to change its attitude about marijuana.

“Our team has contacted several parties and tried to promote our ideas of allowing the people to grow cannabis to boost our economy," he told me. "We’re moving behind the scenes, but moving. We’re trying to contact as many political parties as possible."

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The government was also struck by how much money it could potentially make off legalization, explained Kitty, at the Highlands Network. This, likely more than any actual health-related arguments, was a strong motivator for the junta government.

The Thai government relies far more heavily on so-called consumption taxes—taxes collected from purchased goods—to fund the state budget than countries in the West. An estimated 33 percent of state revenues came from these taxes last year, making it the single largest source of money for the junta. And opening up an entirely new market of taxable goods, like marijuana, would only drive the government's take higher.

"Weed right now, at least in America, is profitable," Kitty said. "There’s a $2 to $4 billion dollar industry in Oregon, and that’s just Oregon alone. There’s also so much money to be made here too, and the government knows it can make lots of money out of this. And they realize that it could actually be good for the people."

Public perceptions about marijuana are also changing. The vast majority of Thais are now supportive of the idea of medical marijuana. A recent poll from the National Institute of Development Administration found that 72.4 percent of those surveyed supported the legalization of medical marijuana. It's as clear as sign as any that national attitudes toward marijuana and drug use are changing in Thailand (the country's justice minister also floated the idea of decriminalizing meth use in recent years, arguing that "the world has lost the war on drugs," another sign that the country may be growing tired of a costly and unwinnable drug war).

“It is a positive shift from policy-making based on morality and ideology to being based on evidence,” explained Gloria Lai, the Asia regional director of the International Drug Policy Consortium. “It is likely that some other countries will follow suit, as there has been some consideration for permitting medical use of cannabis in South Korea, Sri Lanka, and the Philippines already."

In Thailand, the government is intrigued. It sent a team of specialists to Canada to study the local marijuana industry, and the Ministry of Health seems closer than ever before to throwing its support behind the legalization efforts.

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If all goes well, Thailand might legalize the drug entirely, Somyot thinks, a move that would allow for the private production of marijuana for recreational use. The junta's cabinet of ministers has already pushed for amendments to Thailand's drug laws that would allow researchers to run human trials on the effectiveness of cannabis as a treatment for certain diseases.

That bill is currently before the National Legislative Assembly, and, according to experts, it's likely to be passed. Lawmakers are even urging the junta government to step-in and use its powers to push the legislation through into law without a vote—effectively making an end-run around the assembly that could end off a possible election time delay.

And others are already talking about taking that bill even further, to include widespread legalization.

"I have met many people, many politicians who agree, they say 'yes'," Somyot said. “I have heard that some political parties are deciding the policy on allowing people to grow cannabis for commercial purposes."

How did this all happen, I asked. What's behind such a sea change in attitudes regarding marijuana in Thailand? Somyot thinks a lot of this has to do with people's attitudes toward the drug. Like in the United States, the idea of legalizing marijuana is getting more and more support these days. And even in a military-run government like Thailand's, public sentiment plays a role in government policy.

“I think it's the acceptance," he said. "The acceptance from the people. Nowadays I think the people have more impact."

And, according to Somyot, if this legalization plan works in Thailand, the rest of the region could soon follow suit, a move that could effectively change the way an entire region of the world thinks about drugs. This could really be the moment the global fight to legalize marijuana hits a tipping point, as long as it actually happens, he explained.