Who'd have thought? Weed is the one thing we almost agree on.

I was not expecting Supreme Court Justice Clarence Thomas to be the voice of reason on the federal government's continuing and inane classification of cannabis as a dangerous drug with no currently accepted medical use.

But there he was late last month, the author of a five-page statement accompanying the court's decision to turn down an appeal from a medical marijuana dispensary in Colorado.

The dispensary has challenged a provision in the tax code that prohibits businesses that "traffic in controlled substances" from deducting ordinary business expenses from their taxable income. Although the court did not take the case, Thomas had some choice words for the government's illogical approach to pot.

"The Federal Government's current approach is a half-in, half-out regime that simultaneously tolerates and forbids local use of marijuana," Thomas wrote. "This contradictory and unstable state of affairs strains basic principles of federalism and conceals traps for the unwary."

The case at hand, he wrote, "is a prime example."

The dispensary in question, Standing Akimbo, is a 10-year-old Denver storefront serving patients who rely on cannabis to ease what ails them. Many are cancer patients, the store's co-owner Spencer Kirson told me Thursday. He and his partners were disappointed that the Supreme Court did not take their case, he said, but were heartened by Thomas' words.

While federal law still prohibits possession, cultivation or distribution of cannabis, the Department of Justice, Thomas noted, "has sent mixed signals."

Under President Barack Obama, the Justice Department stopped interfering with legalization efforts in states, and every year since 2015, Congress has forbidden the department from spending any money to thwart the implementation of medical marijuana laws.

A majority of states — nearly 40 — have legalized cannabis for medical use. And as Thomas noted, 18 of those have legalized marijuana for both medical and recreational use, including California, whose voters approved the Adult Use of Marijuana Act in 2016.

California, incidentally, became the first state to legalize medical marijuana when voters approved Proposition 215 in 1996. "This thing is a disaster," fumed then-state Attorney General Dan Lungren. "What's going to happen? We're going to have an unprecedented mess." (A mess did not ensue.)

Despite legalization, pot businesses are treated wildly unfairly when it comes to federally regulated areas such as income taxes and banking.

They are forced to conduct all transactions in cash, because credit card companies generally do not permit cannabis-related charges and banks don't want to tangle with the feds. They can't deduct certain business expenses, including rent and employee salaries, from their federal taxable income.

Under the tax code provision that Standing Akimbo is challenging, Thomas wrote, "a business that is still in the red after it pays its workers and keeps the lights on might nonetheless owe substantial federal income tax."

Can you imagine?

In a country where profitable corporations and rich individuals find ever more creative ways to avoid paying federal taxes, forcing a money-losing business to pay more than its fair share is not just outrageous, it's downright un-American.

There are some glimmers of hope that the federal government will eventually liberalize its sclerotic view of marijuana.

In January, Republican U.S. Rep. W. Gregory Steube of Florida introduced a bill, the Marijuana 1-to-3 Act, that would knock pot off the Drug Enforcement Administration's list of most dangerous substances, Schedule I, and list it in Schedule III, the category for drugs that have a currently accepted medical use and a risk of dependence.

In April, the U.S. House passed the SAFE Banking Act, which would allow cannabis-related businesses to access the banking system in states where they are legal and regulated. (This is the fourth time the House has taken on this issue; the first was in 2013.) The current bill passed with bipartisan support — 321 to 101 — and had the backing of 106 Republicans.

In the past, bills like these haven't gotten far — the first bill to deschedule pot was introduced in 1981, after all — but attitudes toward cannabis have changed dramatically in the last decade.

An overwhelming percentage of Americans — 60% according to the latest Pew Research Center survey — say marijuana should be legal for both medical and recreational use. If respondents are asked only whether medical marijuana should be legal, that number soars to 91%.

Only 8% think pot should be illegal in all cases.

At a moment when we are so riven by partisanship and conflict, who would have ever guessed that weed is one thing we can (almost) all agree on?