The nationalism and the protectionism that was built into the Mexican Revolution in 1910 and that characterized the Mexican attitude to the United States for much of the 20th century were difficult to overcome. But that actually has occurred. And the cooperation, trust and confidence that have been built is not something that should be abandoned without great consideration for the potentially grave consequences to the United States.

Every air traveler entering Mexico is vetted against US databases. The air passenger screening system Mexico has in place involves these checks against US national security and criminal data bases. There are plainclothes US officers stationed at airports in Mexico working with Mexican immigration officials to protect the United States. This joint security program has been in place for at least six years and is a huge asset.

The Mexican people are increasingly middle class, and Mexico has substantially become a middle-class society. This is true despite the significant poverty, and the class and geographic inequality that have deep historical roots.

To the extent that President Trump means strengthened border security, I am fully in favor of the idea that the rule of the law, secure borders and public safety should prevail. Drugs should not enter illegally. Migration should take place in accordance with lawful norms and secure and safe procedures.

Walls and barriers alone are insufficient to insure security.

The nationalism and the protectionism that was built into the Mexican Revolution in 1910 and that characterized the Mexican attitude to the United States for much of the 20th century were difficult to overcome. But that actually has occurred. And the cooperation, trust and confidence that have been built is not something that should be abandoned without great consideration for the potentially grave consequences to the United States.

We can't defend the country by looking at the borderline as the first line of defense rather than as the last line of defense. We have to secure the flow of goods and people by engaging with foreign entities. We assure our security by securing the flows as early as we can before they arrive and as far away from our borders as we can.