With a cry of "smoke 'em if you got 'em", Seattle's potheads celebrated under the Space Needle on Thursday as Washington became the first state in the USA to fully decriminalise marijuana.
They were breaking the law – it remains illegal to smoke a joint in public and cannabis is regulated under the Controlled Substances Act at federal level – but police and FBI agents looked on impassively. There were no arrests and no altercations, just shining eyes and a pungent cloud you could smell downtown.
The passage of Initiative 502 made it legal to possess an ounce (28.5 grams) or less of marijuana for personal recreational use. Seattle is one of the most liberal cities in America and police there have adopted an amused, tolerant stance.
An online memo confirmed that officers will write tickets for brazen public offenders, but added that "the police department believes that, under state law, you may responsibly get baked, order some pizzas and enjoy a Lord of the Rings marathon in the privacy of your own home, if you want to".
Colorado will soon follow Washington's lead, once its Amendment 64 is signed into law by Governor John Hickenlooper.
There are already 18 states with medical marijuana statutes in place, making it legal for patients and care-givers to possess the drug. "The momentum is towards trying to take marijuana out of the black market," said Ethan Nadelmann, director of the Drug Policy Alliance. "There are all sorts of innovative approaches to doing that.
"These include medical marijuana, decriminalisation, the Washington/Colorado alcohol control model, but it's all about bringing it above ground where it can be taxed, regulated and controlled."
In the latest CBS poll, opinion was evenly split, with 47% of respondents in favour of legal marijuana and 47% against. But 72% said people should not be sent to jail for possessing cannabis and 83% backed medical marijuana (even though only 29% believed that it is primarily being used by people with serious illnesses such as multiple sclerosis).
"There has been a dramatic increase in support and decrease in opposition in the last seven or eight years," said Nadelmann. In a Gallup poll from 2006, just 36% backed legalising the drug, with 60% against.
So does this mean that prohibition is on the rocks across the United States? Will cannabis become as socially and legally accepted as alcohol within a generation? There is good reason to doubt such claims. California has been taxing and regulating medical marijuana since 1996, but while the drug is on the controlled substances list, it remains a grey legal area for the state's growers and dispensaries.
Wary of being labelled soft on drugs, President Barack Obama has instructed his Department of Justice to take a hard line, despite admitting his own fondness for marijuana as a youth. In a biography by David Maraniss, Obama is portrayed as a leading member of the "Choom Gang" at Punahou School – choom meaning to smoke grass.
"Barry – as he was known – had a knack for interceptions," writes Maraniss. "When a joint was making the rounds, he often elbowed his way in, out of turn, shouted 'Intercepted!' and took an extra hit."
This autumn, federal agents cracked down on pot clubs (dope smoking collectives), showing up in force to threaten them with closure. Oakland's Harborside Health Centre, the largest marijuana vendor in the state, received a tax bill for $2.4 million from the Internal Revenue Service which allowed it none of the standard deductions for payroll or costs available to any other business. Growers in Mendocino, Humboldt and Trinity counties – known as the Emerald Triangle for the number of weed plantations – still take elaborate precautions to conceal their activities, for fear of being busted by the feds.
The United States Attorney for the Western District of Washington, Jenny Durkan, spelled it out in a statement: "Regardless of any changes in state law- growing, selling or possessing any amount of marijuana remains illegal under federal law."
James Doherty, a former prosecutor in Washington, said it will be difficult to enforce the Controlled Substances Act without the help of local law enforcement: "It's still a federal offence, but if federal prosecutors want to enforce the law, they need federal agents running around, charging, prosecuting all these crimes and locking people up. The federal government has always relied on the states to carry the ball in the war on drugs."
Across the country, supporters and opponents of legalised cannabis are waiting to see how the government will respond.
There is no legal way to grow or distribute marijuana in Washington. Under Initiative 502, legislators have until the end of next year to come up with a comprehensive way of taxing and regulating the drug. Colorado is much closer to a solution, because medical marijuana has been legal there for more than a decade.
Each of the 4200 people employed by the industry requires a licence, every stage of the growing and distribution process must be videotaped and trucks carrying the drug must be weighed on departure and arrival.
Under Amendment 64, there will be a 15% excise tax on wholesale marijuana sales, with the first $40m set aside for the construction of public schools. The Colorado Centre on Law and Policy has estimated that the combination of new tax revenues and reduced law enforcement costs could be worth $60m each year to the state.
Washington's Office of Financial Management projected that marijuana could become a $1 billion business in the state, making it the second most important agricultural commodity, behind apples but ahead of milk and wheat. If the federal authorities back off and allow a new regulatory system to get up and running, there are clearly fortunes to be made.
James Shively, a former Microsoft executive, told his local radio station in Seattle that he is in the process of setting up a "premium marijuana" business.
"My great-grandfather, Diego Pellicer, supplied hemp rope made from the marijuana tree to the Spanish armada during the Spanish-American sar," he said. "So I've got marijuana in my blood, so to speak."
He added he had come up with the idea for his new company after taking a few hits from the bong.
"The buzz is in the air. This is a new industry in the making, and it's going to be a giant industry and the state of Washington is going to lead the way.
"What Kentucky became for bourbon, the state of Washington is becoming for marijuana. It's going to be a huge boost to the economy," he said.
California's medical marijuana trade shows how thoroughly commercial the industry could become. On Venice Beach, in Los Angeles, every other shop front promises that "the doctor is in" and will write a prescription for marijuana on the spot. At upscale dispensaries, there are scores of strains available, many with catchy nicknames such as U2, Agent Orange, Northern Lights or Bob Marley Sativa. Edible products include Oaksterdam banana walnut bread and Kiva medicinal chocolate.
"The California marijuana industry is not about providing medicine to the sick," said US Attorney Laura Duffy. "It is a pervasive for-profit industry that violates federal law."
However, it was notable that the busts occurred in cities where regulation is weakest. Supporters of full decriminalisation in California say they will put a proposition on the ballot in 2014 or 2016.
Four states have pending medical marijuana legislation on the books: New York, Ohio, Pennsylvania and Illinois. In Arkansas, a medical marijuana measure was narrowly defeated on election day, winning 49% of the vote.
Not one Senator has publicly spoken out in favour of legalisation, but libertarian congressman Ron Paul has been banging the drum for years, and some well-connected Republicans are calling for the party to follow his lead.
"This isn't really a drug-legalisation issue: it's a states' rights issue and a limited-powers issue," argued Betsy Woodruff in the National Review.
"Supporting the autonomy of Colorado and Washington won't save the conservative movement. But it would be a step in the right direction."
In 1932, Supreme Court Justice Louis Brandeis wrote: "It is one of the happy incidents of the federal system that a single courageous state may, if its citizens choose, serve as a laboratory and try novel social and economic experiments without risk to the rest of the country."
Obama's administration must now decide whether Colorado and Washington ought to be allowed to proceed, in the interests of seeing whether it leads to increased or decreased rates of drug abuse and whether it benefits taxpayers.
"There's going to be lots of people watching, doing studies, surveys and data analysis, but I think the main impact is going to be that people realise this isn't some hare-brained idea from long-haired, pot-smoking kids," said Doherty, the former prosecutor. "This is a real, serious policy issue."