The legalization of marijuana is the next great reversal of history. Perhaps the most demonized substance in America, scientifically known as Cannabis sativa, simply a very fast growing herb, thrived underground as the nation's most popular illegal drug.
Now the tide has shifted: In 1996 California passed the nation's first medical marijuana law, which allowed patients to grow it and use it with a doctor's permission. By 2010, twenty states and the District of Columbia had adopted medical pot laws. In 2012 Colorado and Washington state passed ballot measures legalizing marijuana for adults age 21 and older.
Bruce Barcott, a former Guggenheim Fellow in nonfiction, is a frequent contributor to the New York Times, Rolling Stone, National Geographic, the Atlantic Monthly, Outside magazine, and many other publications. His book is Weed the People: The Future of Legal Marijuana in America.