"Everyone who studies this problem has the same diagnosis," said Benitez of American University. "It's urgent to professionalize all aspects of police work: prevention, investigation, and intelligence against organized crime. The police need more resources, better training and better technology."
But police and judicial reform probably will take years to produce results. Until then, there is the army, an institution that struggles to retain its personnel.
Lieutenants and other low-ranking army officers earn monthly salaries ranging from $400 to $600. Many desert or resign each year to join private-sector security companies. A few join the traffickers.
"A drug-trafficking group can afford to pay a soldier several times what he earns in the army," said Jose Luis Pineyro, a Mexico City specialist on military issues. "There isn't a government in the world that can compete with what drug traffickers can pay."
To keep its elite Special Forces troops from deserting to the drug cartels, as several dozen have done, the army recently raised the monthly salary for soldiers to about $1,100. Pineyro said the cartels simply doubled that amount as the standard pay for their own "troops."
Drug-trafficking groups have been drawn to the area for its fertile soil and convenient geography. The same qualities once made the area the center of an agricultural boom in the 1970s, when thousands of acres of cotton provided work. Water is plentiful, and the port at Lazaro Cardenas is only 90 minutes away.
The boom crops are now opium poppies, which are processed into heroin, and marijuana. Cocaine shipped by sea from Colombia passes through by the ton, U.S. drug experts say. Chemicals from China are cooked into methamphetamine at clandestine labs.
Rugged hillsides and protection money have made drug enforcement impossible. Traffickers take advantage of long-standing family relationships, as well as ambitious residents with few other means of getting ahead.
The so-called Sinaloa, Juarez, and Milenio cartels form one alliance in the region, the Gulf cartel and La Familia another.
"They are people with little education or culture but a lot of money," columnist Ramos said of the traffickers. "Their fights are emotional. They are motivated by anger and pride. And they fight like people with empty stomachs."
One such fight was the May 7 battle on Melchor de Talamantes street. On Wednesday, half a dozen city police stood guard over the one-story brick house where three men and a woman died in the shootout with soldiers.
Locals say that the freshly painted houses in the neighborhood are evidence of the illicit money that is pouring into Apatzingan.
Armando Bustos, the city police officer in charge of guarding the crime scene, said he had lived for seven years in Southern California's San Gabriel Valley, working at a car wash and living with an uncle, before returning home to Mexico.
"Am I scared? The whole world is scared," Bustos, 28, said in English. "I went to Alhambra High School and I'd go back there in a minute if I could. I think I will. This is too freaking dangerous."
Enriquez reported from Apatzingan and Tobar from Mexico City. Carlos Martinez and Cecilia Sanchez of The Times' Mexico City Bureau contributed to this report.