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.

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.

Mexico now has the 13th largest economy in the world. The Organization for Economic Cooperation and Development predicts it will have a larger economy than Germany by 2042.

In the last generation we've moved past a U.S.-Mexico relationship that while friendly on the surface, and demilitarized for the most part, really was not a genuinely cooperative relationship. As a result of the U.S.-Mexico War in the 19th century, and the treaty of Guadalupe Hidalgo in 1848, half of what was Mexico was severed and became much of the western part of the United States. To add insult to injury, most Americans never knew that, and most Mexicans have never forgotten it.

In the course of 25 years, we have developed a constructive relationship with Mexico that was nonexistent before. During the last eight to 10 years there have been continued efforts which have resulted in a strategic alliance with the Mexicans and improved safety and security at the border.

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.

Most people who live at the border or are familiar with the border know that a Berlin-like wall stretching from San Diego to Brownsville is not necessary. And the costs would be prohibitive. And there are places on the border, such as the Arizona desert or the open terrain around the Big Bend in South Texas, where Mother Nature has created her own barrier that is not easily passable. Or if you do pass through it, you are easily detected.