Editor's Note: Since the publication of STRATFOR's 2010 annual Mexican cartel report, the fluid nature of the drug war in Mexico has prompted us to take an in-depth look at the situation more frequently. This is the second product of those interim assessments, which we will now make as needed, in addition to our annual year-end analyses and our weekly security memos. As we suggested in our first quarterly cartel update in April, most of the drug cartels in Mexico have gravitated toward two poles, one centered on the Sinaloa Federation and the other on Los Zetas. Since that assessment, there have not been any significant reversals overall; none of the identified cartels has faded from the scene or lost substantial amounts of territory.