The Gulf Cartel has a solid hold on a swath of the country on the northeast coast (see map here), providing both access to the US and a port for receiving shipments. The emergence of Los Zetas as a competing cartel and sustained government pressure has weakened the Gulf Cartel significantly, and it relies on the Sinaloa Federation’s protection to hold off the Zetas.
The Gulf Cartel and Zetas have fought fiercely over coastal territory. The Zetas launched an offensive in November, after the death of Gulf’s Antonio “Tony Tormenta” Cardenas Guillen, to gain control over Matamoros, a coastal city on the US border that is the key to the Gulf Cartel’s operations.
It became a three-way fight with the Mexican authorities who were fighting both groups. The Gulf Cartel survived the fighting and began smuggling large amounts of cocaine, which nets far more revenue than marijuana, to recoup the losses incurred during the fighting.
While still holding it together, the Gulf Cartel is stretched thin. “The Gulf Cartel is engaged in a large, bloody game of ‘whack-a-mole’ in which its dual opponents [Los Zetas and Mexican authorities] further stretch its resources,” STRATFOR notes.