Marijuana just keeps growing. That's a weak attempt at a punny metaphor for which I apologize (hey, I could have used some variation such as "growing like a weed," so I did exercise a little restraint...), but its deeper meaning is that marijuana is actually outgrowing such cheap jokes and entering the realm where it demands to be taken seriously -- especially by politicians. Marijuana is now the nation's fastest-growing industry. The legal marijuana industry brought in $2.4 billion last year, so it's certainly no longer any sort of laughing matter. That figure represents an increase of a whopping 74 percent in one year's time, and it is estimated that the total legal market could be worth $11 billion as soon as 2019.

This news is all contained in the third annual "State of Legal Marijuana Markets" report from The ArcView Group, described as "a cannabis industry investment and research firm based in Oakland, California." The Huffington Post has a good overview of what the report contains, complete with some very interesting charts projecting the size of the possible future legal marketplace. These projections seem just a wee bit optimistic to me, assuming (for instance) that the following states will legalize adult recreational use either this year or in 2016: California, Nevada, Arizona, Maine, Vermont, Massachusetts, Rhode Island, and Maryland. By 2020, the projection adds Montana, Hawai'i, New Hampshire, Connecticut, New Jersey, and Delaware to this list. This would make a total of 18 states to fully legalize, which (as I said) may be slightly optimistic.

Optimistic or not, though, it's hard to argue against at least some of those states ending their own War On Weed within this time period. Whether it happens that fast or takes a slightly different route, though, the destination should be more and more obvious as the legal marijuana industry continues to grow. The end of this road is pretty stunning, just in sheer numbers:

The huge growth potential of the industry appears to be limited only by the possibility of states rejecting the loosening of their drug laws. The report projects a marijuana industry that could be more valuable than the entire organic food industry -- that is, if the legalization trend continues to the point that all 50 states legalize recreational marijuana. The total market value of all states legalizing marijuana would top $36.8 billion -- more than $3 billion larger than the organic food industry.

So far, this reform effort has taken place at the grassroots level (there I go again with the puns... sorry). All five places where recreational legalization is now on the books (Alaska, Colorado, Oregon, Washington state, and Washington DC) happened via ballot initiatives. Most of the states now considering the idea are also going to happen by the direct expressed will of the voters, although either Vermont or Rhode Island could become the first states to do so through their state legislatures. This marks a turning point, because it means politicians will be less and less able to either flat-out ignore the issue or treat it as some sort of joking matter.

There is already an established marijuana lobby in DC. This is also a sign of growing up: entering the political process by means of campaign donations. Even when the people are leading on a hot-button issue, politicians think they're free to dodge the issue until it starts hitting them directly in the campaign chest. Look at the Democrats' evolution on gay marriage, for instance, and how much more seriously Democratic candidates started to treat the issue once the big gay-rights donors started threatening to turn off the money spigot. You can bemoan the influence of money in American politics all you want from a purist position, but the reality is that any issue with a big lobbying effort is taken a lot more seriously than one with no money behind it. It's a political fact of life, whether you despise that this is so or not. And the marijuana industry is starting to play this game. It will only become more and more effective at doing so as the industry grows, both in size and in stature.

State-level gains on marijuana reform are one thing, but the real battles which remain are going to have to be fought at the federal level. The first skirmish is already happening, because although the voters in Washington DC voted overwhelmingly to legalize recreational marijuana, Congress may think it can get away with vetoing the will of the voters. It will be interesting to see how many Democrats stand up for District residents on the issue.

Most Democratic politicians at the national level might be charitably described as "reluctant" to support drastically reforming federal marijuana laws. But such reforms are going to be absolutely necessary, and the pressure for them to happen is only going to grow. Democrats old enough to remember the "Nancy Reagan era" of the Drug War know that Republicans will in all likelihood level two charges against any Democrats brave enough to call for changes: being "soft on drugs" and "soft on crime." Anyone who thinks these aren't effective political bludgeons probably didn't live through the 1980s.

But if the number of states which have legalized recreational use reaches double digits (as it could very well do in 2016), the pressure is going to mount for national politicians to show some leadership. The people will be leading, and the leaders will have to eventually follow, to put this in bumper-sticker language.

The remaining hurdle for the marijuana industry might be called "normalization." Legal recreational marijuana is now (or soon will be) a reality in four states. What is necessary now is the equivalent of the passage of the Twenty-First Amendment. When federal Prohibition of alcohol was overturned, what happened was exactly what is already taking place now for marijuana -- alcohol laws were changed state by state (even county by county in many places), and we were left with a patchwork of laws across the nation. It took until 1966 before the last statewide alcohol prohibition law was repealed, in fact (in Mississippi).

But while there are indeed still "dry" counties in America, there is an important distinction between current laws on alcohol sales and current marijuana laws. An American citizen can travel anywhere in the country with a couple of cases of beer in the backseat of his or her car and not risk being arrested for possessing alcohol. As long as it's for personal use, as long as the driver hasn't recently consumed any of it, and as long as nobody's trying to sell it illegally, there is no danger of being locked up or the citizen's vehicle being impounded. Liquor store owners, as long as they're legal with the state and county, are allowed to have a business checking account in their local bank. They are also allowed to deduct their business expenses from their taxes. Beer advertisements are allowed to be broadcast even in "dry" counties. While local laws may ban alcohol sales, alcohol possession is not a crime. People growing barley, hops, wheat, potatoes, or any other plant which is made into alcoholic beverages don't have to comply with any onerous regulations controlling how many plants they may grow, which allows the free marketplace to work as intended. None of that is true for marijuana.

The biggest political step that still needs to be taken on the national level is completely divorcing marijuana from the rest of the ill-fated Drug War. Politicians can indeed manage to do this by taking the stance: "Let's spend our drug enforcement dollars intelligently and go after crystal meth and heroin abuse instead of wasting it on marijuana." That is both an effective and a fiscally-responsible argument.

At some point, most likely led by Democrats (although libertarian Republicans could indeed surprise me), it is going to become more of a political liability to fight against marijuana's mainstreaming than it will be a positive political position to take. This could happen rather quickly, in fact (consider that in the past six years, the Democrats went from timidity to full-throated support for marriage equality, led by Barack Obama's own "evolution" on the matter). Especially if six or seven states vote to legalize recreational use during a presidential election year.

Beyond politics, however, the normalization of marijuana use continues in American society, and sometimes from unexpected directions. While marijuana activists were amused that last year's Super Bowl was played between the two teams from fully-legal recreational states (the Broncos and the Seahawks), this year it is even more impressive that ex-stars of the N.F.L. are now publicly calling for the league to change their own rather Draconian attitudes towards marijuana use by their players.

Marijuana users will eventually be as free as beer drinkers in America. That is the end game for marijuana reform. Marijuana may not be sold everywhere in the country, but then neither is alcohol (even eight decades after the repeal of Prohibition). But other than moonshiners, nobody today worries about being arrested for breaking alcohol possession laws. Instead it is treated as a recreational vice with limits on responsible use (drunken driving and public intoxication laws still remain on the books, to put this another way). In a nod to the N.F.L. players' column, I can end here by defining the ultimate measure of when marijuana will be fully normalized in American society: when an advertisement for weed airs during the Super Bowl. Today, the possibility of seeing a Super Bowl ad for Bob Marley brand joints seems pretty far-fetched, during the most-watched television event of the year (with the most-expensive advertising rates). But the marijuana industry is growing so fast that such a thing may become reality a lot sooner than anyone might now predict. The marijuana industry is indeed growing up, and eventually it's going to want a seat at the biggest advertising table the country has to offer.

-- Chris Weigant

Cross-posted at The Huffington Post

Follow Chris on Twitter: @ChrisWeigant