Just after posting that last bit I found a very interesting exchange of letters and a response by Huntington here on the FP website. (they annoyingly ask you to register)

Here is what my old advisor, Wayne Cornelius wrote:

Wayne Cornelius
Gildred Professor of U.S.-Mexican Relations
Director
Center for Comparative Immigration Studies
University of California, San Diego
San Diego, Calif.

For nearly 30 years, I have watched the best and brightest young men—and more recently, their sisters, wives, and daughters—leave high-emigration rural communities in central Mexico to seek jobs and higher wages in the United States. They bring much more human capital to the table than their parents and grandparents, who were welcomed by the United States as essential workers during two world wars. And because of modern communications, including the Internet, these latter-day migrants are far more assimilated into U.S. culture than their predecessors, even before beginning their journey. They are hardly “contemptuous” of American culture, as Huntington maintains. Young Mexicans today are all too willing to shed their own cultural traditions and embrace U.S. values, such as consumerism.

Viewed from this on-the-ground perspective, Huntington’s assertions about the poor quality of Mexican migrants to the United States and their alleged resistance to cultural integration seem bizarre. If anything, his arguments are more applicable to the flow of Mexican migrants to the United States in the middle of the 20th century than they are to more recent arrivals. Economists such as Gordon Hanson and Pia Orrenius have shown that the least-skilled, least-educated Mexicans today are far less likely to migrate.

Moreover, female migrants are more educated than males, and their representation in the U.S.-bound migration flow has increased sharply in the last 15 years.

Huntington claims to be concerned mainly about inadequate cultural assimilation among Mexican and other Latino immigrants, but most of the non-anecdotal data that he cites as evidence of their failure to assimilate relate to economic marginality. He implies that because the low-skilled people now being imported in such large numbers from Mexico are ill-equipped to deal with the modern U.S. economy, a crisis of assimilation is inevitable. Certainly, current gaps between people of Mexican origin and all Americans in educational attainment, job skills, and homeownership are worrisome, but the intergenerational narrowing of these gaps is significant. Huntington’s claims notwithstanding, it is unproven that occupying a step lower than native-born Americans on the economic ladder today will produce unacceptably poor labor market and cultural integration outcomes tomorrow. The most rigorous research, by immigration scholars such as Alejandro Portes and Rubén Rumbaut, demonstrates that Spanish dominance fades quickly in the second U.S.-born generation of Latinos and essentially disappears in the third.

What is indisputable is that Mexican migrants in the United States—including unauthorized ones—are a more stable population than in previous eras. This development is a direct consequence of the U.S. government’s post-1993 strategy of “concentrated border enforcement,” which has made no appreciable dent in illegal immigration but has sharply reduced circular migration between Mexico and the United States by making return migration prohibitive. Given Huntington’s belief that Mexican immigration is ruining the “Anglo-Protestant” America that he celebrates, will he cast his vote for weaker border enforcement?