On Tuesday, August 24, Mexican Marines discovered 72 bodies of murdered immigrants (58 men and 14 women) at a farm near the town of San Fernando in the Northeastern state of Tamaulipas, about 120 miles south of Brownsville, Texas on the Rio Grande.

The victims, although not all have yet been identified by nationality, were not Mexican citizens, but themselves undocumented immigrants traversing Mexico together on the way to the United States.

Mexico’s National Security Director, Alejandro Poiré, tentatively identified them as coming from El Salvador, Honduras, Ecuador and Brazil, according to the newsmagazine Milenio.

Evidently a notorious drug gang called “Los Zetas” (“the Zs”), which according to Gustavo Castillo of the Mexico City daily La Jornada and others say controls San Fernando, had kidnapped the immigrants with the idea of enslaving them as part of their criminal operations, but the migrants refused. One of the migrants escaped to a nearby Marine post. After a firefight with the Zetas, the Marines found the corpses.

The original Zetas were started by rogue military officers trained at the U.S. Army School of the Americas in Fort Benning, Ga. At first they hired out as enforcers for the Gulf Cartel, but subsequently formed their own extremely violent cartel. They now contest the Gulf Cartel’s control of the Northeastern border area.

That drug cartels kidnap undocumented immigrants and demand that their relatives in the United States or in Mexico pay ransom in exchange for their freedom (and their lives) is not new. This has happened with arrested undocumented Cuban immigrants, for example, with police buses being waylaid and the immigrants they were carrying turning up safe and sound on U.S. soil.

Non-Mexicans are somewhat more vulnerable than Mexicans in these situations as they are already in Mexico illegally. Corruption in Mexican police and immigration agencies makes the matter significantly worse; many non-Mexicans report that they are robbed, beaten and shaken down in their trip through Mexico. But Mexican citizens headed for the U.S. have been kidnapped for ransom also.

Reasonable people might see this latest bloody incident and a number of others like it as a sign that the country’s war against drug cartels is spiraling out of control. But Mexico’s conservative President Felipe Calderon caused jaws to drop by claiming that this mega-death incident proves that his strategy of militarizing the struggle against drug cartels is successful. According to his logic, groups like the Zetas are on the ropes in the drug war, and thus are forced to try out new rackets like kidnapping undocumented immigrants for ransom.

But even a busted cuckoo clock like Calderon gives the right time twice a year, and in this case he has made two eminently reasonable requests from the United States on which the government has simply not acted: To crack down on the some 7,000 gun shops that operate near the U.S.-Mexican border, which are a source of weapons with which the cartels often outgun Mexican police forces; and to do a better job of attacking our own country’s massive appetite for the narcotics, which have made the cartels rich.

There are other things that can and must be done:

First, there has to be a comprehensive immigration reform in the United States that creates safe and legal mechanisms of immigration. If this is complete enough, it will put the kidnappers out of business.

Secondly, developing countries like the ones these immigrants come from need to be able to provide jobs and economic security for their poorest people.

Of the four countries that Poiré says were represented in the 72 fatalities, in fact three (Brazil, El Salvador and Ecuador) have left of center governments that are working to improve conditions for poor farmers and workers. The United States should be supporting these efforts.

Honduras was doing so also, but in June 28 its progressive government was overthrown by a military coup and since then landowners and employers have been doing what they can to reverse the previous government’s pro-worker and pro-farmer policies, as well as unleashing repression. The United States has not, as far as anyone can tell, been putting pressure on the new Honduran government to reverse this.

Finally, fighting drug abuse and trafficking as a “war” has to be abandoned. Drug abuse has to be seen as a medical and social problem, and treated with medical help, counseling and educational efforts. This is how our tax money should be spent.

Photo: This image released by Mexico’s Navy shows the site where 72 bodies were found in San Fernando, eastern Mexico, Aug. 24. (Mexico’s Secretary Navy/AP)