U.S., Mexico unite to go after drug cartels

MEXICO CITY — To avenge the arrest of their leader, Mexican drug cartel commandos went on a rampage last summer across the lawless state of Michoacan, seizing 12 Mexican police officers and dumping their corpses in a pile beside a busy highway.

The slaughtered federal agents, it later emerged, had something in common: All had been vetted and trained by the U.S. government to work alongside its antinarcotics agents. Officials said the American connection made them high-value targets for the cartels, who are lashing back against a military crackdown involving unprecedented cooperation between the two countries.

After decades of mistrust and sometimes betrayal, Mexican and U.S. authorities are increasingly setting aside their differences to unite against a common enemy. According to interviews in Washington and Mexico City, the two countries are sharing sensitive intelligence and computer technology, military hardware and, perhaps most importantly, U.S. know-how to train and vet Mexican agents.

The newly robust partnership is still risky, uneasy and freighted with old suspicions.

U.S. law enforcement officials said it is being forged with the assurance by the U.S. State Department that Mexico's weak law enforcement agencies will overcome a history of incompetence and corruption, and that the closed ranks of the Mexican military, which operates with impunity, can get past its hostility to outsiders.