The capture of Joaquin "Chapo" Guzman, head of Mexico's Sinaloa cartel, is worth celebrating on both sides of the border. Photographer: Susana Gonzalez/Bloomberg
The capture of Joaquin "Chapo" Guzman, head of Mexico's Sinaloa cartel, is worth celebrating on both sides of the border. Photographer: Susana Gonzalez/Bloomberg

For Mexican President Enrique Pena Nieto, the capture of Joaquin "El Chapo" Guzman, head of Mexico's Sinaloa cartel and arguably the world's most notorious drug lord, is as momentous (and Hollywood-ready) as the killing of Osama bin Laden was for U.S. President Barack Obama. By nabbing "Shorty," Pena Nieto has both made his country safer and improved his political standing.

Unfortunately, the parallels don't stop there. Bin Laden's death marked not the end of al-Qaeda but its evolution into a more dispersed and no less deadly threat. Guzman's arrest likewise highlights a shift in Mexico's criminal landscape from one populated by a handful of big cartels to one teeming with scores of smaller and more violent groups that rely on not just drug-running, but also extortion and kidnapping.

The fight against these groups will be long, arduous and door-to-door. It is also -- primarily -- a Mexican fight, which is why it would be a mistake to move Guzman to the U.S., where he faces multiple federal indictments. Pushing for extradition would not only undermine the kind of U.S.-Mexico cooperation that produced his arrest, but also deny Mexico the chance to show it can hold such criminals to account and undermine Pena Nieto's credibility and commitment.

The war goes on, obviously, but the tactics need to change. When the state of Michoacan's government was overrun by the Knights Templar drug gang and self-styled vigilantes, Pena Nieto's administration in effect took over the state, deploying the military and billions of dollars in assistance. Pena Nieto cannot afford to do that in every state that faces a severe crime problem.

The solution is to promote the rule of law at the local level. Although Mexico has begun a transition to a new justice system based on adversarial public trials with oral arguments (as opposed to a closed-door system based on written arguments), only one-third of the population is now covered by the switch, which is supposed to be complete by 2016. The reform of state and local police has yet to gain real momentum. Building public trust in the judiciary and law enforcement is a critical challenge: Some of the highest of Mexico's very high homicide rates have been recorded in places with low social capital -- disrupted family and community networks in cities such as Ciudad Juarez, which has seen a dislocating influx of workers to its border factories.

If the U.S. wants to help, it could expand its assistance to Mexico for criminal justice reform. Or it could step up inspections to stanch the southbound traffic of guns that doubtless included some of the 97 large guns, 36 handguns, 2 grenade launchers and one rocket launcher seized during his arrest. Right now, the U.S. interdicts only a tiny fraction of trafficked firearms heading to Mexico. Or it could step up its anti-money-laundering enforcement. (You can walk across the U.S. border into Mexico with hundreds of thousands of dollars stored on prepaid cards.)

So by all means let law enforcement officers on both sides of the border celebrate Guzman's arrest. Then they can get back to work on meeting the new threat posed by those who will surely follow in his wake.

To contact the editor responsible for this article: David Shipley at davidshipley@bloomberg.net.