Mexico has spent more than a decade using the military to fight drug cartels.
But a top US military-intel official says their technique hasn't worked at all.
In fact, it's made matters worse by destabilizing the country.
Army Gen. Robert Ashley is the head of the Defense Intelligence Agency.
He says that by removing the leaders of the five key cartels, they've splintered into 20.
In other words, the "kingpin strategy" has led to even more violence.