This year's 4/20 follows successful legalization campaigns in California, Nevada, Maine and Massachusetts, which join Alaska, Colorado, Oregon and Washington as states that allow recreational marijuana. More than half the states allow medical marijuana.
But it remains illegal under federal law. Attorney General Jeff Sessions this month ordered a review of marijuana policy to see how it may conflict with the President Donald Trump's crime-fighting agenda, and Homeland Security Secretary John Kelly recently called marijuana "a potentially dangerous gateway drug that frequently leads to the use of harder drugs." That's a view long held by drug warriors despite scant evidence for its validity.
Sixty percent of adults support legalizing marijuana, according to a Gallup poll last fall, and two-thirds of respondents in a Yahoo/Marist poll released this week said marijuana is safer than opioids.
Undermining regulatory schemes in legal pot states could prompt a backlash that would hasten the end of federal prohibition, said Vivian McPeak, a founder of Seattle's Hempfest.
"We're looking at an attorney general who wants to bring America back into the 1980s in terms of drug policy," McPeak said. "I'm skeptical they can put the cannabis genie back into the bottle."