Gisela Mota became the mayor of Tenmixco, Mexico–in Morelos, the state of a hero of mine, Emiliano Zapata–on Friday. She’s seen here at her swearing in. Yesterday, Saturday, drug cartel gunmen shot her to death outside her home.

I hate drugs because they are so much more insidious than bullets. So it’s jarring when a little research reveals that recent marijuana legalization may have been the most effective tactic yet used against the Mexican cartels. They are losing a significant part of the immense flow of dollars that sustains them. They are hurting.

So was a recovering heroin addict I knew once. But he was having a far, far easier time than the guy trying to kick his—legal—prescription painkillers. That man was going to pieces. Both  were sick men; I’m not sure why they’re alive, but not this vital young woman. None of this makes sense to me.

Two more things, in our relationship with Mexico, don’t make sense to me, either:

• In the wake of NAFTA, American corn producers dumped their product on the world market a decade ago. They generated a wave of foreclosures on small Mexican farms and the resultant migration, now subsiding, that Mr. Trump wants to end with a wall.

• If you know our history of alcohol abuse, from the very beginning of the nation (it was, ironically, corn alcohol at the beginning), then you know that we are not noted for our impulse control. So it’s not supply, but instead American demand for drugs that helps to fuel the cartel crossfire that kills so many innocent Mexicans.

“Poor Mexico,” the poet Octavio Paz once wrote. “So far from God, so close to the United States!”  Few nations are so tightly linked yet so insistent on denying their kinship. The first victim of the Mexican Revolution was an El Paso housewife hanging out her laundry, killed by a bullet that crossed the border. More than a century later, the cartel murders represent the worst violence since the Revolution, which killed a million people, or one of every ten Mexicans.

Somehow, the drug violence must stop. I don’t know how to stop it. But I know that this not what Zapata died for when he, too, was assassinated in 1919. I know, looking at Gisela’s image, that the Mexican people have been cheated again, robbed of a young woman of promise in the young part of a year that now promises nothing at all.