In the grotesque wars that pit Mexican armed forces and drug cartels against each other and civilians who get in their way, the Zetas cartel plays a fearsome role. Born of U.S.-trained Mexican special forces who began working as muscle for the Gulf drug cartel, the Zetas rapidly expanded by employing methods aimed at terrorizing opponents and civilians alike: decapitations, public hangings, and mutilations.

Although the otherwise dominant Sinaloa federation of Mexican drug cartels is responsible for more than 80 percent of drug war murders in that country, the Zetas’ exotic cruelty gets more media coverage. Last month, alleged Zeta men torched a casino in Monterrey, killing 52 people inside, mostly older women. A policeman and the brother of Monterrey’s mayor have also been implicated in the crime, illustrating how Mexican officials are often participants in the same organized crime politicians say they are fighting.

The Zetas

The Zetas’ gruesome tactics have earned them a place on the United States’ short global list of criminal syndicates, and as a central target in $1.5 billion of U.S. military aid to Mexico since 2008.

And the Zetas are expanding their operations. A recent report by InSight Crime details the Zetas’ move into Guatemala and provides an important understanding of the Zetas’ military and commercial logic. Their income comes not just from drug profits, but by taxing all legal and illicit commercial activity in the territory that they control. Those who don’t pay the Zetas’ “tax” face their terrible and certain wrath. The Zetas draw on their military training and access to high-powered weapons to enforce such territorial advances.

The Zetas have also recruited former members of Guatemala’s feared commandos, known as Kaibiles. The Kaibiles gained a reputation for cruelty during Guatemala’s attempted genocide in the 1980s. In July, four Kaibiles were convicted for their part in the brutal Dos Erres massacre of 1982, in which the soldiers raped women, smashed babies’ skulls, and murdered 251 Mayan villagers. The Zetas apparently saw the Kaibiles’ methods as useful to their own expansion.

For more than two decades, U.S. assistance to the Guatemalan army was partially banned because of these atrocities. Now, the United States is aiding the Guatemalan army, including providing a barracks renovation by the Army Corps of Engineers in Poptun, a remote town in the Central American country’s northwestern Petén province that hosts the Kaibiles training facility. U.S. Embassy officers who visited the Poptun base in October 2009 wrote a glowing assessment of U.S. Special Forces living with Kaibiles forces. Last September, a squad of 40 U.S. Marines trained Kaibiles soldiers on the base.

“The drug cartels are made up of Guatemalans who are guided by the cartels, such as the Zetas and the Gulf. Many of the low-ranking [cartel] officers were trained in the same military school that is located in Poptun,” a government official told Global Post. Former Kaibil soldiers “follow orders, kill, use military strategies to persuade people,” the official said.

Now, according to InSight Crime, the Zetas have established a base in the same small jungle town where the U.S. military has been upgrading facilities and training soldiers from a unit linked to the Zetas.

What better demonstration is there of the Drug War’s perverse logic? The U.S. military trains poorly paid young men with few work options to kill, which plays directly into the game of narcotraffickers.

It’s time to re-cast U.S. drug policy in Mexico and Guatemala and stop supporting military training programs that end up aiding drug traffickers. Reducing the demand for illegal drugs would be more effective than arming the “good guys” in a futile and violent fight to stamp out the supply.

Instead of contributing to a bloodbath in Latin America, Washington should deal with U.S. drug abuse as the public health problem that it is.