chilango
Ha! Ha! Armageddon
If it was a legalised industry the cocaine would be transported directly from the Andes to America and wouldn't transit Mexico at all. It would also be in the hands of large corporations - like coffee for example.
If it was legalised why would gangsters get involved in the industry any more than in coffee growing/processing/distribution?
The gangsters/politicians/rich capitalists/state are pretty much interchangeable in Mexico as are their footsoldiers. You think the maquiladores for example are less gangsterish?

The US is without a doubt headed for it's own ditch but so is Europe. If the Mexicans want to build a wall to keep the illegal gringos out it's fine by me. 
I can only speak for this part of the country where the population is more than 2 per square mile. 