Marijuana isn’t "Bill and Ted’s Excellent Adventure" or "Friday" or "Beavis and Butthead" anymore. In fact, those references are so old that many of you may not even remember them, or may not have even been born when they were popular.

Marijuana isn’t even represented by the classics like "Cheech and Chong" or hippies and comfy couches. Thanks to states grabbing the reins and exerting their prerogatives, marijuana is now big business. Dispensaries are doing billions of dollars in business and since California started the trend in 1996 by passing a state law legalizing medical marijuana. More states are quickly joining the pot revolution and even legalizing recreational marijuana.

However, there is still a big problem: the federal government.

Revenues from the domestic marijuana industry are expected to grow from $6.7 billion in 2016 to more than $21 billion by 2021. And that is just the start. When you look at the economy dynamically, that $21 billion is the tip of the iceberg. With that kind of growth, employment increases not only in the marijuana industry it increases in other markets. As people in the marijuana industry start making more money, and the people in jobs that support the industry start making more money – then they spend more money and the growth continues. That all means jobs and tax revenue that states don’t currently have. But as the economic growth numbers grow, so will the need for assurances from the federal government that they won’t intercede in the growth of the market.

President Trump made repeated promises to respect the will of people in states that have consented to medical marijuana while on the campaign trail, great! Even better, as pointed out in a Reason article earlier this year, Congress has been trying to send those signals too:

In 2014, Congress passed the Rohrabacher-Farr amendment, which prohibits the Justice Department from prosecuting medical marijuana businesses in states that allow it. Naturally, the AG wants Congress to pass an appropriations bill removing that language. Now's the time for the real federalists in Congress to stand up and stand by Rep. Dana Rohrabacher, R-Calif., and Sen. Patrick Leahy, D-Vt., who want this restraint on federal interference to continue.

Yet, those are not the signals that Attorney General Jeff Sessions is sending, and his actions are undermining the work of the president and Congress. By sending a memo in January directing all U.S. attorneys to enforce current federal marijuana laws and pursue prosecutions related to marijuana activities — despite what voters of many states have voted for — Attorney General Sessions is taking a step backwards. This is the opposite direction of the “ Cole Memo,” which the Department of Justice put out in 2013, which largely left marijuana regulation to the states.

And while the AG’s strategy is ill-advised (at least from my point of view), Sessions' move might be defensible if it were an attempt to get Congress to return these choices to the states. But, Sessions didn’t just stop with the reversal of the Cole Memo – his Justice Department also sent a letter to Congress demanding that the Rohrabacher-Farr language, which prevents medical marijuana prosecutions, be lifted.

Individually, you may or may not be a supporter of marijuana – although about 60 percent of Americans are – but most people would agree that if a business is legal in a state then it should, for example, be able to use the banking system at least within that state. But thanks to federal policy, simple everyday banking is still one of the problems hampering the growth of the marijuana industry.

These policies don’t just hurt the marijuana industry. They hurt everyone and take away rightful powers from the states.

I understand at least half of Sessions' argument. A law is a law. But proposing to fix the problem by restricting states’ powers is not the right solution. The right solution is for the Congress to pick up the AG’s challenge and officially return the jurisdiction of this whole fight back to the states.

Fortunately, Congress is going to have an opportunity in the middle of March to re-affirm the Rohrabacher-Farr amendment. Congress is going to have to either continue preventing Justice from going after medical marijuana laws in states or not. If Congress refuses, it would be another giant step backward for federalism, and an even bigger step backward for the economic momentum the Trump administration has created.

Charles Sauer (@CharlesSauer) is a contributor to the Washington Examiner's Beltway Confidential blog. He is president of the Market Institute and previously worked on Capitol Hill, for a governor, and for an academic think tank.

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