Sensing that Sessions didn’t have a leg to stand on, Cory Gardner, the junior senator from Colorado, responded by declaring that he would block all Justice Department nominees until the Trump administration changed course. And in a phone call last week, Trump assured the senator that he intended to do just that. As if to pour salt on Sessions’s wound, according to Gardner, the president also pledged to support federal legislation that would formalize the right of state governments to establish their own marijuana markets, presumably with only minimal federal oversight. Trump is famously unreliable, and I don’t doubt that passing such a law would take some doing. Nevertheless, it is hard to deny that Sessions’s gambit backfired. Gardner shrewdly played the president against one of his least-favorite lieutenants, and so it seems he will get his way.

Gardner’s role in this contretemps is revealing. Not long ago, he campaigned against legalizing the recreational use of marijuana in his home state, as one might expect from a law-and-order Republican. Yet as support for marijuana legalization has increased, and as the marijuana industry in his home state has grown by leaps and bounds, Gardner has shrewdly repositioned himself as its champion. To be sure, he isn’t as zealous a champion of the cannabis industry as, say, his Senate colleagues Cory Booker, Ron Wyden, or Kirsten Gillibrand, who have sponsored a bill that legalizes marijuana at the federal level, or Rand Paul, who is similarly inclined. But Booker, Wyden, and Gillibrand are liberal Democrats, which makes their enthusiasm something of a dog-bites-man story. Paul, meanwhile, is an avowed libertarian, who often takes pointedly contrarian stands. Gardner, in contrast, has impeccable conservative credentials, and he typically makes his case on federalist grounds: Despite his past misgivings about liberalizing marijuana laws, he defends the right of Coloradans to do so if they choose. His stance is perfectly tailored to neutralize objections from older conservatives who might otherwise balk at the thought of legal weed. Among GOP senators, Gardner is as mainstream as it gets. If he is for legalization, how bad could it possibly be? Many Republicans will be asking themselves exactly that question, especially as cannabis entrepreneurs and investors woo them with campaign contributions and, in some cases, the prospect of future employment. Former House Speaker John Boehner, for instance, has recently signed on as a director of Acreage Holdings, a sprawling cannabis business, and its competitors will surely be looking for notables of their own.

Lost in all of this political maneuvering is the small matter of whether state governments are serving the public interest in their headlong rush to liberalize marijuana laws. The fundamental challenge, as Caulkins argues, is that cannabis is a dependence-inducing intoxicant, and a cheap one at that. In Washington state, a marijuana-legalization pioneer, he observes that the cost per hour of cannabis intoxication “has fallen below $1, cheaper than beer or going to the movies.” This is despite the fact that the state’s marijuana growers and distributors operate in a grey zone—legal at the state level, but not legal at the federal level—which leaves them ineligible for the federal tax deductions to which all more straightforwardly legal businesses are entitled. Gardner, Paul, and Wyden have together sponsored legislation that would correct this little oversight, putting cannabis businesses in a far more favorable position. And if marijuana could be cultivated at industrial scale, using all of the tools and technologies American agriculture has to offer, well, we can expect the cost per hour of cannabis intoxication to fall further still.