People should remember that Mexican migration is now at a net negative. More Mexicans are leaving through deportation and voluntary return than are entering the United States legally and illegally.

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.

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.

Mexico has become a robust democracy with a robust press and an active legislature. It has gone from being a sending country for migrants to a transit country, and increasingly a receiving country for migrants in its own right.

The work the Mexicans are doing in terms of migration control on Mexico's southern border is crucial to our own border security.

Our security in a global world must be looked at on a continental basis.

Not only are the numbers of migrants entering the United States at the lowest levels in a generation, but they are now largely Central American. Four out of five border-crossers detained in South Texas are Guatemalan, Honduran or Salvadoran. They are driven by violence and poverty in their home countries and the desire for family reunification.