Mexican bordertowns have long had a "sleazy" reputation. Drug trafficking and violence are certainly not new to these areas: Tijuana, Ciudad Juarez, Matamoros, etc. The Herrera family of Durango peddled heroin in the 1950s when the "perfect dictatorship" of the PRI (Revolutionary Institutional Party) was probably at the peak of its power. The Herrera family's tentacles were all over Mexico and penetrated the United States, reaching as far north as Pittsburgh. In 1975 the PRI welcomed the DEA, which started operating in Mexico. So basically there's nothing new, it has simply intensified and is compounded by the customary corruption, which recently has reached into the highest levels of government.
The reader from Riverside is fairly accurate in his assessment. Mexio faces the daunting task of how to combat unrelenting drug trafficking and corruption/impunity (among the three major parties) on the one hand and, as a nascent democracy growing out of a putrid single-party state, guaranteeing constitutional protections when its citizens and institutions have not had much experience in these matters. Already there are constituional issues about their army patrolling the streets and the Mexican Human Rights Commission (Comision Nacional de Derechos Humanos) has 120 cases under investigation.
If legalizing and controlling drugs is a social experiment worth trying, it could only work if both Mexico and the US act simultaneously. The last thing we want to see is a police state on either side of the Rio Grande.