The challenges of the Mexican government are so immense when it comes to battling the powerful drug cartels. For one, the cartels have so much money that they have been able to pay off judges and cops and prosecutors. And it’s not isolated, it’s systemic. 
The voice, belonging to a cartel spy, then broadcast the soldiers’ route through the city, turn by turn, using the same military language as the soldiers.
“They’re following us,” Col. Juan José Gómez, who was monitoring the transmission from the front seat of an olive-green pickup truck, said with a shrug.
The presence of the informers, some of them former soldiers, highlights a central paradox in Mexico’s ambitious and bloody assault on the drug cartels that have ravaged the country. The nation has launched a war, but it cannot fully rely on the very institutions — the police, customs, the courts, the prisons, even the relatively clean army — most needed to carry it out.
The cartels bring in billions of dollars more than the Mexican government spends to defeat them, and they spend their wealth to bolster their ranks with an untold number of politicians, judges, prison guards and police officers — so many police officers, in fact, that entire forces in cities across Mexico have been disbanded and rebuilt from scratch.
