I take back everything I wrote about security at the beginning of my trip.
In the Toluca airport the bag that was to go "debajo", in the cargo section of the plane, was thoroughly checked and blue fasteners were place on each zipper.
My computer needed to be taken out of my carry on.
I was asked for photo ID.
When I arrived back in Chihuahua there were several soldiers with guns and a big dog. They were in search of drugs. Airport security checked to ensure none of the blue fasteners had been tampered with, and I needed to produce my airline ticket.