All the US has to do is tell Mexico that they consider cartel activity to be a state assisted act of war against the US and refusal to stop them will be considered an act of war, to which the US will take the intiative to clean it up for them.
That’s what should happen in a US where politicians were not being bribed by the cartels themselves to not enact laws.
With our record of military losses around the world do you want to risk losing a war to the cartels on the border - and I am not being sarcastic. I am being sardonic.