Senate Minority Leader Charles E. Schumer (D-N.Y.), right, talks with Sens. Ben Sasse (R-Neb.), center, and Tom Cotton (R-Ark.) on Capitol Hill on May 18. (Mark Wilson/Getty Images)

Sen. Ben Sasse (R-Neb.) is one of a small crop of recent Republican arrivals on Capitol Hill who, by the standards of Capitol Hill, are fairly hip. Granted, that’s a very particular standard, but Sasse’s age (he’s 45) and background (he was president of Midland University in Fremont, Neb., before winning election to the Senate) have made him an unusually modern voice among the typically staid, clipped voices we normally hear in Congress. [Another we’d put in this group is Rep. Justin Amash (R-Mich.), recognizing that this is subjective.]

So while this is an uncommonly casual tweet for a member of the Senate, it’s on-brand for Sasse.

Sen. Charles E. Schumer, with rumpled suit and windblown hair. The lackadaisical attitudes of all three men. The sense of informality in a formal environment. It’s on the mark. Internet hero Darth did what he does.

The joke is also particular to a particular cultural niche: People who slip out of fancy weddings to smoke a joint. Ivy League-educated Nebraskan Sasse clearly knows that niche well, whether or not he himself slipped out of a wedding with that intent.

But, look. It’s impossible to ignore the contrast between Sasse’s casual joke about marijuana and the efforts of others in the Senate — and in the Trump Justice Department — to treat drug offenses in the harshest possible terms.

The drug war has always been overlaid with issues of class and race. A kid slipping out of an expensive wedding to smoke a joint earned a different punishment than did a kid stopped with a joint on a street in Crown Heights. Under the Obama administration, the Department of Justice tried to reduce that discrepancy, including moving away from enforcing mandatory minimum sentences — which, given that the Crown Heights kid was more likely to be arrested than the wedding kid, increased the odds that the former would end up serving a lengthy term in prison. President Barack Obama put a focus on granting clemency to those sentenced to extended drug sentences, offering more commutations of sentences than any president in a century.

A week ago, Attorney General Jeff Sessions announced that he would instruct prosecutors to pursue the most severe penalties available in criminal cases — including stiff penalties in drug cases. Sessions himself has been critical of efforts to decriminalize marijuana, saying that medical marijuana in particular has been overhyped. He gave a speech in March in which he addressed marijuana use.

“I reject the idea that America will be a better place if marijuana is sold in every corner store,” he said. “And I am astonished to hear people suggest that we can solve our heroin crisis by legalizing marijuana — so people can trade one life-wrecking dependency for another that’s only slightly less awful. Our nation needs to say clearly once again that using drugs will destroy your life.”

Experts would be quick to point out that the effects of marijuana and heroin differ greatly — as does the extent to which individuals can grow dependent on either drug.

Stricter sentencing laws are a key reason that the federal prison population ballooned from the 1980s on, rising from fewer than 50,000 in 1985 to over 200,000 in 2015.

Under Obama, the number declined for the first time in decades. Sessions’s policies promise to reverse that trend. Nearly half of those in federal prison are there for drug offenses.

This is the environment in which Sasse’s joke lands. It’s a perfectly fine joke, and the last thing that anyone who pays attention to politics should do is unfairly criticize a politician who makes a joke that doesn’t feel as though it was pilfered from Jack Benny’s reject pile. But it highlights a critical discrepancy within the Republican Party — and between Congress and the American public. Medical marijuana, for example, is approved of by more than 9 in 10 adults, according to an April poll from Quinnipiac University.

Anyway, Sasse liked Darth’s Photoshop.

As of writing, it has not been liked by the attorney general.