There was a lot of drug-war hand-wringing in the U.S. leading up to President Barack Obama ’s visit to Mexico this week. That’s because Mexican President Enrique Peña Nieto is in change-the-conversation mode: he wants the world, especially Washington , to focus less on his country’s awful drug violence — some 60,000 narco-related murders in the past seven years, with little sign of abating — and more on its robust economic potential. The fear in some Washington circles is that Peña Nieto and his Institutional Revolutionary Party (PRI), which in its dictatorial 20th century heyday was every drug lord’s, or best buddy, is putting the fight against Mexico’s vicious cartels on the back burner.

And I would say to Obama: Even if that’s the case, it shouldn’t spoil your two days in Mexico City.

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That doesn’t mean I favor abandoning the fight against los narcos. I’m just saying that if the past seven years have shown us anything, it’s that it doesn’t matter whether Peña Nieto ratchets up that fight (as his predecessor did) or dials it down, or whether Washington pumps more or less aid into it — not as long as police and judicial institutions remain dysfunctional in Mexico and demand for illegal drugs remains insatiable in the U.S. Which is why, if Obama and Peña Nieto are the smart politicos they’ve proved to be, they’ll realize that the two most important developments in the drug war over the past six months took place not during any interdiction operation but on Election Day last November in the U.S. and on Tuesday, April 30, in Mexico.

The Mexican news first, because I think it’s potentially more consequential. Tuesday night, the Mexican Senate convincingly passed a telecommunications-reform bill, pushed by Peña Nieto and already approved in the lower Chamber of Deputies. It’s aimed at dismantling the monopolies that smother competition in Mexican industries like telecom, where the América Móvil company headed by tycoon Carlos Slim, the world’s richest man, controls more than 80% of the nation’s land-line market and more than 70% of its cell-phone market. The legislation packs sharper enforcement teeth and “prevents monopolies from being able to resort to the constant, endless appeals litigation they use to avoid paying fines and sanctions,” as Peña Nieto described the bill to me in a TIME interview shortly before his inauguration in December.

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So why does this impact the drug war? Call it a leap of faith, but if this reform really does turn out to be a monopoly-buster — and, this being Mexico and the ruling party being the PRI, it’s better to take a wait-and-see approach — it will be striking evidence that rule of law has a chance to take root in Mexico. Slim and the other Mexican monopolists targeted in the bill aren’t drug lords. But for decade after decade, they’ve been getting away with an unjust practice that modern democracies usually penalize if not thwart. Stripping them of their notorious impunity could go a long way toward fostering the kind of culture of legality that in turn nurtures more professional and less corrupt courts, judges, prosecutors and especially investigative cops — the judicial backbone of any credible fight against organized crime.

Washington ought to know this already after its happier experience more than a decade ago in Colombia — where the billions the U.S. poured into antidrug aid bore fruit largely because Colombia finally made the effort to strengthen rule of law. Shannon O’Neil, a senior fellow at the Council on Foreign Relations, aptly pointed out in her 2011 article “How Mexico Can Win the Drug War, Colombia’s Way” that Colombia emphasized “professionalizing the police and reforming [the] judicial system.” It did this via nothing less than a “transformation within” the country that saw its elites finally take responsibility for public security, something Mexico’s hypernegligent ruling class is still reluctant to do. (In fact, as evidenced by one recent scandal, Mexico’s rich and powerful still seem more interested in shutting down restaurants that don’t give them good tables.) “More than foreign security aid,” O’Neil wrote, “this is what Mexico needs today: an investment by [its] elites in the safety and well-being of all its citizens.”

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If I were Obama, and if I were truly interested in the Mexican drug war’s long-term success, I’d be focused less on Peña Nieto’s interdiction scorecard at the moment and more on the Mexican Senate’s roll call Tuesday night. And I’d hope like hell that it really is the first installment of the Mexican elite’s own, long-overdue investment in rule of law.

As for what happened on Election Day last fall in the U.S., if I were Peña Nieto I’d urge Obama to do on the federal level what the states of Colorado and Washington did: legalize marijuana. (Mexico should do the same, by the way.) That would do two things: First, deprive Mexico’s drug cartels of more than a third of the $30 billion or so they make each year. Second, save the U.S. the estimated $10 billion it wastes every year chasing down a drug that’s no more harmful than alcohol when used in moderation. It can then steer that money to drug-demand-reduction efforts like rehab services, which studies show do more to ease the drug plague than conventional supply-side interdiction does.

Let’s focus our cross-border angst on raising Mexican rule of law and reducing American appetite for blow, smack and meth. Because if those efforts fail, all the other drug-war hand-wringing we do is meaningless.

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