In this Dec. 19, 2014, photo, sales associate Matt Hart uses a pair of chopsticks to hold a bud of Lemon Skunk, the strain of highest potency available at the 3D Dispensary in Denver. Colorado emerged as the state with the second-highest percentage of regular marijuana users as it began legalizing the drug. (David Zalubowski/AP)

Republican Chuck Grassley and Democrat Dianne Feinstein are united in their opposition to ceding the war on drugs. Last week, they sent a joint letter to Secretary of State John Kerry and one to Attorney General Eric Holder expressing their concerns that the legalization of marijuana in some states is in direct conflict with international conventions.

Tom Angell, chairman of Marijuana Majority, completely agrees. But how to remedy that contention? That’s where their agreement ends.

Senators Grassley of Iowa and Feinstein of California, in their letters to Kerry and Holder, argue that the Obama administration’s decision not to interfere with states legalizing recreational marijuana makes it difficult for the U.S. to then defend “compliance” with the United Nations Conventions on Narcotics treaty, which says marijuana should be limited to scientific and medical use.

In the fall, Assistant Secretary of State William Brownfield said there should be a flexible interpretation of the treaty. That, the senators wrote to Kerry, “could create a harmful precedent that would allow state parties to implement policies that legalize other, even more harmful drugs, without recourse.”

Angell agreed there is an inconsistency. “When the U.S. has legal marijuana, it makes it difficult for U.S. officials to go around the world and say they should continue to prohibit marijuana,” he told the Loop. But unlike the senators, advocates for legalizing the drug would prefer the U.S. support amending the U.N. treaties to be more lenient.

“We both see the same effect, we see what is coming down the line,” Angell said, referring to changing marijuana laws. “We like it, they don’t like it. We’re winning, they’re not.”

There is one more area in which Angell and drug reformers side with the senators. In the Grassley and Feinstein letter to Holder, they ask that Justice compile data on the “overall effect” of allowing states to legalize marijuana – such as whether it’s easier for minors to get pot.

“Yeah, we’d like to see that data all compiled in a nice neat package,” Angell said, predicting that it would show that legalizing pot generates tax revenue, reduces the size of the drug black market and would generally support the case for legalization.

Or, maybe it would show Feinstein’s right that weed is a gateway drug.

And yes, it is not lost on us that a senator with the last name “Grassley” is spearheading an anti-marijuana effort.