To those of the white race who look to the incoming of those of foreign birth and strange tongue and habits for the prosperity of the South, were I permitted, I would repeat what I say to my own race: “Cast down your bucket where you are.” Cast it down among the eight millions of Negroes whose habits you know, whose fidelity and love you have tested in days when to have proved treacherous meant the ruin of your fireside.

Washington and other progressives were joined in opposition to unrestricted immigration by yesteryear’s “social conservatives”—citizens who feared that an influx of Catholic and Jewish immigrants would undermine the country’s Protestant culture. However, even in combination, progressives and social conservatives were no match for the business interest, which time and again blocked popular legislation to control immigration.

Two developments tipped the scales in the early 1920s, leading to the single occasion in American history when Congress acted to reduce the total level of legal immigration. First, under the leadership of Samuel Gompers, himself an immigrant, the American Federation of Labor made an end to mass migration from Europe one of the key demands of the country’s first nationally effective labor organization. Second, and probably of greater importance, anarchists and socialists began showing up among the postwar flood of immigrant workers into American cities. Fear of social and political instability moved enough businessmen into the restrictionist camp to enable passage of the 1920s quota legislation.

Today, as in the past, large-scale immigration is supported by business interests and opposed by most social conservatives. What is strikingly different today is the extent to which progressive forces, including congressional Democrats, civil-rights leaders and even segments of organized labor, have sided with big business in opposing most measures to restrict immigration. This loss of a restrictionist faction on the left to balance the open-borders faction on the right is key to understanding why a nation now confronted with falling water tables, a collapsing infrastructure, failing schools, declining wages and widespread unemployment is on the verge of sanctioning what amounts to the largest wave of legal immigration in American history.

When progressives initiated the 1965 reforms that triggered the current wave of mass migration, they were not deliberately aiming for greater diversity. On the contrary, Senator Edward Kennedy testified, “Our cities will not be flooded with a million immigrants annually.” Senator Robert F. Kennedy argued that the elimination of quotas “can have no significant effect on the ethnic balance of the United States.” They were wrong. But Ted Kennedy went on to embrace the ensuing demographic revolution, as have contemporary liberals like Joel Kotkin, who predicted in his 2010 book The Next 100 Million: America in 2050 that the “staggering amalgam of racial, ethnic, and religious groups” that we are destined to become would bring about “the construction of a new civilization.” Amid the celebration, more conservative voices, such as Pat Buchanan in his 2011 Suicide of a Superpower, deplored the abandonment of our historic ethnic center of gravity, whose values and habits (notwithstanding many shortcomings) fostered political stability, economic success and individual freedom unparalleled in human history.

AS WRITERS on the left and the right debate whether white Americans should celebrate or deplore their impending minority status, they seldom reflect on the implications for Hispanic Americans of their impending majority status. In so large a group, one naturally encounters a remarkable range of talent and perspectives. However, an accumulating mound of data gathered by Hispanic scholars indicates that as much as half of the Hispanic population, far from forming the nucleus of a confident new middle class that will set a fresh tone for another American Century, are coalescing into a new underclass.

What most distinguishes the booming, immigration-driven Hispanic community from non-Hispanic whites (and also from the much smaller but equally booming Asian immigrant community) is uneven educational attainment, a handicap that stubbornly persists from generation to generation. In 2008, UCLA sociology professors Edward Telles and Vilma Ortiz completed an exhaustive analysis of intergenerational progress among Mexican Americans entitled Generations of Exclusion. Not surprisingly, they reported that first-generation Hispanic citizens outperformed their parents, who often had not completed grade school, but educational progress in the second, third and even fourth generations had been static or even reversed itself. Among other striking conclusions, the professors also found that more than a quarter of fourth-generationMexican Americans were not graduating from high school and that between the third and fourth generations the percentage graduating from college had declined from 14 percent to 6 percent (compared to 35 percent of non-Hispanic whites). In 2010, Carola and Marcelo Suárez-Orozco, codirectors of immigration studies at NYU, documented in Learning a New Land: Immigrant Students in American Society the extraordinary challenges of educating children in the many schools where Hispanic and other immigrant children are now a majority of the student body, including lack of parental support, ethnic self-segregation and fear of violence.

This educational deficit has had deleterious consequences, as measured by the government’s “National Vital Statistics Reports” and its periodic “American Community Survey” and “Current Population Survey.”According to these sources, Hispanic immigrants are significantly more likely to live in poverty and to lack health insurance than their white native counterparts. The likelihood that poverty will pass to the next generation is high, since half of Hispanic children are born out of wedlock. What’s more, in 2010 University of California professors Patricia Gandara and Frances Contreras argued in The Latino Education Crisis: The Consequences of Failed Social Policies that encouraging reports of higher Hispanic rates of graduation from high school often did not account for Hispanics who never entered high school in the first place. They warned that “as a group, Latino students today perform academically at levels that will consign them to lives as members of a permanent underclass in American society. Moreover, their situation is projected to worsen over time.”

Academic stagnation in so large and rapidly expanding a segment of the population has some sobering implications for our nation’s standing in the world. The fact that U.S. students score worse on standardized tests than their peers in many foreign countries is widely known. ExxonMobil’s “Let’s Solve This”campaign warns that “the Program for International Students Assessment [PISA] ranked U.S. students 17th in the world in science and 25th in math.” PISA is a project of the Organisation for Economic Co-operation and Development that tests fifteen-year-olds in over sixty countries every three years. The 2009 test results are summarized in the U.S. Department of Education’s “Highlights from PISA 2009: Performance of U.S. 15-Year-Old Students in Reading, Mathematics, and Science Literacy in an International Context,” which includes an ethnic breakdown of U.S. scores.

Few educators will be surprised that Asian Americans had the highest PISA scores, followed by non-Hispanic whites, Hispanics and African Americans, in that order. More will be surprised to learn that in only one Asian location (the city of Shanghai) did students score better than Asian Americans, in only one European country (Finland) did they score better than non-Hispanic whites and in no Latin American country did students score better than Hispanic Americans. African American students also scored higher than students in the only African country that participated in PISA (Tunisia). Thus, although U.S. students on averagerank below the top-scoring Asian and European countries in the PISA tests, this says less about the relative quality of our educational system than about the relative diversity of our student population.

The academic performance of Hispanics as a group compared to other ethnic groups is not easy to explain, indeed no easier to explain than the differing achievement levels of, say, Korean Americans compared to Filipino Americans or Jews compared to gentiles. However, U.S. immigration policies must shoulder some of the blame. The problem with our policies is not that we admit too many immigrants from countries with low PISA scores; the problem is that our immigration law discriminates across the board against talent and achievement.

The experience of Cuban immigration is enlightening. Prior to the 1980 Mariel boatlift, most Cuban immigrants were middle-class refugees from Fidel Castro’s Communist regime. On average, these Hispanic immigrants have flourished, as have their children and grandchildren. When I was an undergraduate at Yale, and “diversity admissions” were just getting off the ground, one of my new Hispanic classmates told me that he and other students filling the “Hispanic quota” were amused to discover that most of them were the offspring of well-to-do Cuban professionals, not the children of underprivileged Mexican Americans.

But Cuba was not unique in having a large, well-educated middle class. Mexico, the source of most Hispanic immigrants, has millions of successful entrepreneurs and professionals who have embraced an ethic of work and learning and who are prospering within the limits imposed by crime, corruption and other local impediments to upward mobility. Most under the age of fifty are fluent or nearly fluent in English and (in my experience) are more cultured than their American counterparts. Had the U.S. government deliberately set out to increase the Hispanic share of the U.S. population, it could easily have done so by recruiting hundreds of thousands of the “best and brightest” from Mexico and other neighbors to the south.