Drug policy feels very unsettled right now. The war on drugs was a failure. But so far, the war on the war on drugs hasn’t entirely been a success, either. Take Oregon. In 2020, it became the first state in the nation to decriminalize hard drugs. It was a paradigm shift — treating drug-users as patients rather than criminals — and advocates hoped it would be a model for the nation. But then there was a surge in overdoses and public backlash over open-air drug use. And last month, Oregon’s governor signed a law restoring criminal penalties for drug possession, ending that short-lived experiment. Other states and cities have also tipped toward backlash. And there are a lot of concerns about how cannabis legalization and commercialization is working out around the country. So what did the supporters of these measures fail to foresee? And where do we go from here? Keith Humphreys is a professor of psychiatry at Stanford University who specializes in addiction and its treatment. He also served as a senior policy adviser in the Obama administration. I asked him to walk me through why Oregon’s policy didn’t work out; what policymakers sometimes misunderstand about addiction; the gap between “elite” drug cultures and how drugs are actually consumed by most people; and what better drug policies might look like. Mentioned: Oregon Health Authority data “Why are there so many illegal weed stores in New York City? (Part 1)” by Search Engine “Why are there so many illegal weed stores in New York City? (Part 2)” by Search Engine Book Recommendations: Drugs and Drug Policy by Mark A.R. Kleiman, Jonathan P. Caulkins and Angela Hawken Dopamine Nation by Anna Lembke Confessions of an English Opium Eater by Thomas De Quincey Thoughts? Guest suggestions? Email us at ezrakleinshow@nytimes.com. You can find transcripts (posted midday) and more episodes of “The Ezra Klein Show” at nytimes.com/ezra-klein-podcast. Book recommendations from all our guests are listed at https://www.nytimes.com/article/ezra-klein-show-book-recs. This episode of “The Ezra Klein Show” was produced by Annie Galvin. Fact-checking by Michelle Harris, with Kate Sinclair and Mary Marge Locker. Our senior engineer is Jeff Geld, with additional mixing by Aman Sahota and Efim Shapiro. Our senior editor is Claire Gordon. The show’s production team also includes Rollin Hu and Kristin Lin. Original music by Isaac Jones. Audience strategy by Kristina Samulewski and Shannon Busta. The executive producer of New York Times Opinion Audio is Annie-Rose Strasser. Special thanks to Sonia Herrero.