Of all the many ways Trump’s proposed border wall would royally disrupt all kinds of issues in immigration and trade, the cannabis market might not be the most important, but it is one of the more interesting.

While the wall isn’t coming up yet (or probably anytime soon, and maybe never) it has already  got experts looking at the complex relationship between U.S. and Mexican cannabis markets.

Once upon a time around the turn of the millenium, marijuana traffic across the border was mostly one-way, with large shipments of inexpensive low-quality cannabis coming north from Mexico to virtually every market in the U.S. But the days of brick-packed schwag were numbered. As the quality and legality of U.S. cannabis has increased in the last two decades, so the demand for Mexican weed has shrunk to the size of a little brown seed.

VICE reports that just since 2016, DEA seizures of cannabis trafficked into the U.S. from Mexico has dropped 24.7 percent by weight.

“What is pretty clear at this point is that the good old days of sending truckloads of marijuana to the United States are long gone,” security analyst Jaime Lopez said. “The Americans have taken more of the market in the States over the last ten years, which has dried things up for the major [drug] organizations.”

But that doesn’t mean that the two countries are done trading illegal weed. In fact, there’s still a thriving black market import/export business on both sides of the border.

There is a high demand for U.S. weed in Mexico, particularly near the border, according to The Huffington Post, and the country is also importing American extracts and vape cartridges.

And the cartels may be down in the weed game, but far from out. The DEA’s most recent National Drug Threat Assessment report says that Mexico is still our largest supplier of black market cannabis, with 500,000 kg seized by the DEA in 20,000 busts last year alone.

But they’ve also been adapting to compete with the high-quality product made by U.S. cultivators. A source told VICE that Mexican cartels have been upping their game, using the latest cultivation techniques to produce high-quality flower for Mexicans by Mexicans in regions including Sinaloa.

“I have customers who go to California saying that they tried the dispensaries up there and they found that the flowers we provide down here are better quality than the stuff they are growing in the US,” said a street dealer named Jose.

Innovations on both sides of the border, thriving businesses, competitive pricing, higher quality product. Dang, someone should study the illegal weed business before they draft up the new NAFTA agreement.

Photo via Flickr user Brooke Binkowski