Hit men, pistols tucked in their pants and walkie-talkies strapped to their belts, move freely in this city of sorghum farmers and cattle ranchers, dropping off their ostrich-skin boots with shoeshine boys in the city's plaza and stopping at local bars for a beer.
The openness with which they operate -- in Miguel Aleman and countless other towns across Mexico -- reflects the drug cartels' grip on this nation of nearly 100 million people, and the power they have gained as the top supplier for the US' US$65 billion illegal drug habit.
Mexico's drug gangs have been highly successful in the past two decades, gradually replacing Colombian gangs in the US to control the profitable distribution of cocaine from coast-to-coast. Colombia remains the world's largest producer, but Larry Holifield, the DEA's director for Mexico and Central America, said that Mexican cartels are now the most powerful in the world.
In 2003, Mexican traffickers supplied 77 percent of the cocaine that entered the US. Last year, it was 92 percent, Anthony Placido, the top DEA intelligence official, told a congressional panel in June. The other 8 percent moved through the Caribbean.
Mexican gangs also dominate the growing methamphetamine trade, producing 53 percent of the drugs on the market in "super-labs" in Mexico as the US tightens its laws. Much of the rest is made in clandestine labs in California, also run by Mexicans, US officials say.
And as has been true for nearly 100 years, Mexico is the biggest marijuana supplier to the US and produces nearly half the heroin consumed north of the border, behind only Colombia.
The drug trade permeates life in Mexico. In Miguel Aleman, drug traffickers boost the local economy and rule with a combination of fear and awe, threatening or bribing anyone who dares to try to stop them.
In this city of 35,000 across from Roma, Texas, hit men are easily identified by their bulletproof pickup trucks and sport utility vehicles.
The traffickers have lookouts at every entrance to the city and informants on bicycles looking for anyone suspicious, townspeople say. They will photograph newcomers, including reporters, and question strangers.
The traffickers "speed through the street, drive against traffic and run red lights. But here, no one says anything to them," said a businessman who requested anonymity for fear of reprisals. "Here, they are the law."
Soon after taking office in 2000, President Fox reorganized the Attorney General's office and tried to make the Federal Agency of Investigation, Mexico's equivalent of the FBI, more professional.
But Cabeza de Vaca told a Mexican Senate Commission in August that the agency, one of the few trustworthy law enforcement bodies in Mexico, is now corrupted.
In neighboring Guatemala meanwhile, the arrest in September of three former members of an elite counterinsurgency group raised fears the Gulf Cartel may be trying to recruit them to its infamous hit team, the Zetas, led by deserters from an elite Mexican army unit. The Zetas use Miguel Aleman as a base, residents say.
The counterinsurgency group was notoriously brutal during Nicaragua's civil war. Its three veterans and four other people were arrested near Mexico's border with Guatemala carrying six large-caliber rifles and 1,600 rounds of ammunition.
Vasconcelos, Mexico's top anti-narcotics prosecutor, said the Zetas needed the Guatemalans because so many of its members had been arrested or killed.