Poll analyst Nate Silver notes that the percentage of Americans who favor marijuana legalization hit or exceeded 40 percent in three recent surveys (by Zogby, CBS News, and Rasmussen Reports), a level of support that seems to be unprecedented. "There has been a long, slow-moving upward trend in favor of legalization since roughly 1992," Silver says. He projects that if the trend continues (which, in light of the public opinion setbacks "during the Just Say No years of the 1980s," it might not), support for legalization could reach 60 percent in 13 or 14 years, at which point "things might get interesting," since "my guess is that we'll need to see a supermajority of Americans in favor of decriminalizing pot before the federal government would dare to take action on it."
Even before then, we could see significant movement at the state level, which would require no direct federal action—in fact, just the opposite. All the federal government would have to do is step back (as the Constitution requires) and allow states to experiment with different approaches. President Obama's promise to stop undermining state medical marijuana laws, assuming he follows through on it, is a step in this direction. So is the Massachusetts ballot initiative that made possessing up to an ounce of marijuana a citable offense punishable by a $100 fine, a legal change that attracted support from 65 percent of voters in November. Interestingly, California NORML, which commissioned the Zogby poll, reports that it found support for marijuana legalization is already near 60 percent on the West Coast (but adds that "the significance of this margin is questionable due to the relatively small number of respondents"). Since the vast majority of marijuana arrests are made under state law, this may be where the real action is, although allowing production and sale for recreational purposes, as opposed to decriminalization of possession or legalization of medical use, would require a level of federal forbearance not seen since the Marihuana Tax Act of 1937.