He may be right -- now, in perhaps the clearest sign of the group's decline, the Familia has reportedly lost its tight hold on the lucrative methamphetamine trade. This has traditionally been the largest source of revenue for the criminal organization. According to the Associated Press, the rival Sinaloa Cartel has taken advantage of the Familia’s weakened state to seize control of meth production, and is expanding on a massive scale. As evidence, the report says that a haul of more than 400 metric tons of precursor chemicals, used to produce meth, that were seized from a warehouse in Queretaro last July belonged to the Sinaloans.

Even more telling than the sheer bulk of chemicals was the way in which they were organized; when police raided the warehouse they found its contents neatly stacked by forklift into separate categories, suggesting that the group has a well-developed industrial process for making and transporting methamphetamine.

This is a classic illustration of the so-called hydra effect, or balloon effect -- the process by which each blow a government strikes against one organized criminal group simply allows another to rise and take its place. Following to this theory, targeting individual groups will usually only cause production to shift location or change hands. In this case, the cartel taking over the meth trade, Sinaloa, happens to be the most powerful in the country, which does not bode well for U.S. efforts against this highly addictive substance.

According to one anonymous U.S. law enforcement official in Mexico who spoke to the Associated Press, the Sinaloa Cartel has the potential to surpass the Familia’s meth-exporting efforts, as the group already has an extensive supply chain for bringing cocaine, heroin and marijuana into the United States. "Although La Familia has distribution points in the U.S. ... they don't have the distribution network that Sinaloa Cartel has," said the official.

What’s more, demand for Mexican meth in the U.S. has gone up in recent years. As the Wall Street Journalreported recently, the Mexican military raided 103 clandestine methamphetamine labs during the first six months of this year, which amounts to a 25 percent increase from the same period in 2010. Meanwhile U.S. border officials seized a record 5,588 kilograms of meth along the border last year, up from 3,602 kilos in 2009. Officials have already seized that much so far this year, and are set to surpass last year’s record.