Much of the fighting in Mexico can be attributed to turf wars between rival gangs.
Mexico has at least eight separate cartels, which all maintain billion-dollar trafficking routes.
To better understand who is fighting — and over what — check out this map by Stratfor.
For more on the Sinaloa cartel — considered one of the largest and most powerful cartels in the Western Hemisphere — take a look at this excellent series from the Los Angeles Times. The coverage includes an interactive cocaine road map that traces how drugs are smuggled across the border.
And to understand how the Mexican cartels, la Cosa Nostra and the Yakuza fit together, here's a map of the global underworld from Wired.
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