If the war on drugs had ended and the root causes of the cartels were gone, but they were refusing to give up power without a fight, then maaaaybe I could approve of a scenario where the military intervened to break that stronghold. But that's not what's being proposed here.
If we send in the military, we turn Mexico into a war zone, terrorize it's populace, and then leave as a new cartel forms to fulfill the void of business requirements left by the old one. It would accomplish less than actively choosing to do nothing.