The real problem is the Mexican government that allows the cartels to exist. The cartels are no more than drug dealers with big guns and a few shitty, barely armored vehicles.
Mexico can at any point request the necessary equipment and intelligence support to go after and destroy every major cartel organization.
They won’t, because too many people in the government have been paid off. AMLO himself has been paid off in the exact same way many notable Mexican government officials who are now sitting in a US prison have.
What really needs to happen is the US government needs to tell the Mexican government that relations are going to get downgraded and former Mexican officials involved in the drug trade who leave office and lose diplomatic immunity will have warrants put out for their arrest.