Explaining the Violence

Via Mexfiles, the UN has found that Mexico cut marijuana production by around 40 percent from 2007 to 2008. Marijuana accounts for an estimated 60 to 70 percent of Mexico's drug profits, so that amounts to an industry-wide 25 percent decline in revenue in one year! Talk about an economic crisis; that's simply astounding. Such a drop had to lead to violence, as well as a spike in other crimes like extortion and kidnapping. Policy makers should be wary of such radical alternations of the industry. I'm not sure if Calderón's people were aiming for a specific target, nor do I have much of an idea of what an ideal annual drop-off might be (between 5 and 10 percent?), but they should aim to not have a 25 percent revenue reduction in profits in one year. Even if you believe in drug prohibition, to reduce any large industry by 40 percent in one year is bound to create serious disruptions, and said disruptions will inevitably be violent when it comes to drug traffickers. 

Update: In comments, Malcolm Beith digs a little deeper into those numbers: 

i knew something struck me as wrong about this calculation about marijuana production decline. the reason: the UNODC (which released its latest report in June) uses two sources for 2007 and 2008 production. the second, the 15,800 tons figure, is from State Dept. the second, for the year before, is 27,806 tons. but that is based on a questionnaire submitted directly to the mexican gov't.
interestingly, the State Dept's figures come from the PGR too, but in their report (released in feb. and from which the UN took its second figure) there is no production estimate for 2007. but there is one for 2006, and that is 15,500 tons. 27,806 tons would be a huge anomaly for 2007, so my guess is that someone fudged the UN figure for 2007, to make it look like there was a huge drop – thanks to the drug war effort, of course.