Thailand Navigates a Messy Transition to Legalizing Weed

Bangkok’s Khao San Road has been the heady gateway to Southeast Asia for generations of backpackers. Flip-flopped arrivals are met with a sensory cacophony: blistering sunshine, the pungent waft of red chili hitting smoldering woks, and, for the more reckless, a smorgasbord of mind-tweaking drink and drugs procured down back allies and dimly lit bars. Saccharine marijuana smoke was never far away, nor were tales of hapless foreigners hauled off to the city’s infamously fetid jail, dubbed the “Bangkok Hilton,” for smoking a mere joint.

But times are changing on the Khao San Road. On June 9, Thailand became the first country in Asia—and only the third in the world, after Canada and Uruguay—to decriminalize cannabis nationwide. (In the U.S., cannabis is federally prohibited but can be consumed recreationally in 19 states and the District…