The place industrial cannabis is not found yet, Fine points out, is in the above­ground American economy, thanks to its listing as a Schedule I narcotic. The Drug Enforcement Administration’s official stance is that it has no medical value at all: “Smoked marijuana has not withstood the rigors of science — it is not medicine, and it is not safe.” O.K., Fine seems to say, but tell that to the doctors with evidence of its ability to shrink tumors and ease the effects of chemotherapy; or to the seniors of Orange County who depend on medical marijuana to treat their arthritis, and the doctor who uses it to treat his glaucoma; or to the 30-year-old Iraq war veteran with the shrapnel injuries who thanks God every day for this drug. It is prescription drugs that are now the leading cause of fatal drug overdoses — more than 26,000 each year. Also each year, over 23,000 Americans die of alcohol-related causes. None have died from cannabis alone.

As I said, the issue is loaded. And yet the side that has all the load never seems to win in America. The ending of “Too High to Fail” — spoiler alert — is a real bummer. Just as Fine was about to send the manuscript to his publisher in November 2011, the feds cracked down in Mendocino. The 9.31 program was essentially abandoned, and the local, participatory democracy Fine immersed himself in for a year was pushed back underground.

He should have seen it coming. Halfway through his adventure, Fine was pulled over by a state trooper when he left the friendly confines of Mendocino and crossed into Sonoma County — where it’s cool to get high on wine, but not on pot. Fine was doubtful that anyone in California actually used the old war-on-drugs tactics until this incident, but it was a reminder that some people are still in battle mode.

Relating how he was taken into custody, Fine describes something he calls “Panzer’s Paradox” — basically, the fact that “when it comes to distribution, there is no uniformity in cannabis legal interpretation now,” as William Panzer, a lawyer specializing in cannabis defense, says. (Panzer was an author of Proposition 215, the medical-marijuana act passed in California in 1996.) Fine boils down the difference between a cannabis-friendly county and an unfriendly one to “the career ambitions or personal cannabis views of the local D.A. and sheriff.”

He also paraphrases “The Art of War”: “If a war is ill conceived at its core, it can’t be won.”