So much for Donald Trump’s claim to be a supporter of states’ rights. He’s a pick-and-choose advocate at best, as proven when Attorney General Jeff Sessions rescinded an Obama-era policy that allowed for the growth of the legal marijuana industry.

What’s pro state’s-rights about threatening an industry that’s been legalized in more than half of the country — 29 states, to be exact?

Yet that’s exactly what the administration’s move last week threatens to do. By giving U.S. attorneys discretion over whether to crack down on the legal marijuana industries in their states, Sessions and Trump started a process that could lead to greater federal government control over Nevada and other states where voters have approved legalization of marijuana.

Someone should remind Trump what he said about marijuana during an October 2015 campaign stop in Northern Nevada.

“The marijuana thing is such a big thing. I think medical should happen — right? Don’t we agree? I think so,” he said. “And then I really believe we should leave it up to the states. It should be a state situation ... but I believe that the legalization of marijuana — other than for medical because I think medical, you know I know people that are very, very sick and for whatever reason the marijuana really helps them — … but in terms of marijuana and legalization, I think that should be a state issue, state-by-state.”

So way back then — all of 14½ months ago — Trump seemed have a different take.

That happened to be the right one.

The majority of Americans long ago came to believe that federal laws and policies related to marijuana were outdated. So once a couple of states pioneered their way toward legalization, others quickly caught on. That includes in Nevada, where sales of recreational marijuana have outpaced projections.

Sessions’ attitude about the drug — which he immortalized with his 2016 statement “good people don’t smoke marijuana” — is so out of touch that it belongs in “Reefer Madness,” not in 21st century American politics.

Sessions can be as pious as he wants, but a lot of good Americans not only smoke marijuana but realize that the nation’s long-standing ban on the drug has not curtailed its availability or, as evidenced by the fact that legal sales have gotten off to a roaring start, its popularity. Not only that, but many good Americans have recognized that the nation’s marijuana laws are a shameful example of institutionalized, systematic racism, given that they have resulted in a disproportionate number of blacks being arrested and punished for crimes involving the drug.

Enter the legalized marijuana industry, which offered a constructive way to battle the drug cartels, generate tax revenue for the betterment of public schools and other governmental operations, provide medical relief and decriminalize use of a substance that millions of Americans from across the socio-economic spectrum were enjoying recreationally despite it being illegal at the federal level.

To their credit, several Nevada leaders reacted to Sessions with a roar of disapproval.

“I will fight for businesses that are legally operating in states, contributing to tax bases, & creating jobs,” Rep. Dina Titus, D-Nev., tweeted. “We don’t need a crackdown. We need to protect states’ rights, respect the voice of voters, and pass laws to prevent this from happening again.”

Others offered more measured responses. Attorney General Adam Laxalt, a candidate for governor, said he opposed legalization of recreational marijuana but had pledged to defend it were it approved by voters.

Sen. Dean Heller, R-Nev., said: “Knowing Attorney General Sessions’ deference to states’ rights, I strongly encourage the (Department of Justice) to meet with Governor (Brian) Sandoval and Attorney General Laxalt to discuss the implications of changes to federal marijuana policy,” he said.

It’s worth stressing to Nevada leaders, Republican or Democrat: The voters in this state have spoken, and they support the industry. That being the case, their elected representatives need to fight for it.

They also need to battle for the medical marijuana patients who have begun buying the drug to ease the pain of cancer treatment, contend with opioid addiction and deal with a wide range of maladies.

Taking away the drug from those individuals isn’t just senseless, it’s cruel.

It’s little surprise that Trump, who was willing to deny health insurance to children, would attack adults who need medical marijuana.

Trump lied on the campaign trail, and with this move is dancing on the end of a string pulled by a few wealthy donors who want marijuana attacked.

That being the case, there will probably be no choice but to address the issue through the courts should a crackdown occur, and by pressuring Congress to finally reform the nation’s archaic marijuana laws.

What can’t happen is for Nevada leaders to let Sessions and Trump lift one finger against the state’s legal marijuana industry without a fight.

Editor’s note: Brian Greenspun, the CEO, publisher and editor of the Las Vegas Sun, has an ownership interest in Essence Cannabis Dispensary.