Opinion

What if the Mexicans stop coming?

America has been peopled by vast surges of migration — from the British Isles in the 18th century, from Ireland and Germany in the 19th century, from Eastern and Southern Europe in the early 20th century, and from Latin America and Asia in the last three decades.

Going back in history, almost no one predicted that these surges of migration would begin — and almost no one predicted that they’d stop when they did.

Thus when the 1965 Immigration Reform Act was passed, almost no one predicted that we’d have massive immigration from Mexico. Experts told us that immigrants came in large numbers only from Europe.

Wrong: From 1980 to 2008, more than 5 million Mexicans legally entered the country, and Mexicans account for about 60 percent of the estimated 11 million illegal immigrants here.

Policymakers have assumed that the flow of Mexicans would continue at this high level. But now evidence is accumulating that this vast migration is ending.

The Pew Hispanic Center, using Census statistics, has estimated that illegal Mexican entrants have dropped from 525,000 annually in 2000-04 to 100,000 in 2010.

“The flow has already stopped,” Douglas Massey of Princeton’s Mexican Migration Project recently told The New York Times. “The net traffic has gone to zero and is probably a little bit negative.” One reason is the deep recession and slow economic recovery here. Tens of thousands of construction jobs have disappeared. Foreclosures on mortgages that should never have been granted have been especially high among Hispanics.

State laws, like Arizona’s requirement of the federal e-Verify system to check on immigration status of new hires, have clearly had some effect. The cost of crossing the border illegally has risen sharply.

The Pew Hispanic Center estimates the 2010 illegal population at 11.2 million, down from the 2007 peak of 12 million and about the same as in 2005. It’s probably lower today.

Even more important, Mexico has changed. Its birth rate has fallen from 7 children per woman in 1971 to 3.2 in 1990 and 2 in 2010.

Mexico has finally become a majority middle-class country, former Foreign Minister Jorge Castaneda argues in his recent book “Mañana Forever?” It has more cars and TV sets than households now, and most Mexicans have credit cards and cellphones.

A boom in higher education, especially in technical schools, has led to increasing numbers of well-educated Mexicans who have no need to go north to live a comfortable and even affluent life. Mexico has grown its way out of poverty.

The historic experience has been that countries cease generating large numbers of immigrants when they reach a certain economic level, as Germany did in the 1880s. Mass migration from Puerto Rico, whose residents are US citizens, ended in the early 1960s, when incomes reached a third of those on the mainland.

All of which has implications for US policy. It seems clear that tougher enforcement measures, like requiring use of e-Verify, can reduce the number of illegals here. Returning to Mexico is a more attractive alternative than it used to be.

Plus, the desire of legal immigrants to bring in collateral relatives under family-reunification provisions is likely to diminish. That means we can shift our immigration quotas to higher-skill immigrants, as is now done by Canada and Australia.

Such a change would be in line with the new situation. Mexican immigrants have tended to be less educated and lower-skill than immigrants from other Latin or Asian countries. Lower Mexican immigration means fewer low-skilled immigrants. Employers of such immigrants may have to adjust their business models, which they may already be doing. Government, however, adjusts more slowly.

President Obama has been calling for immigration legislation similar to what President George W. Bush sought, geared to a status quo that no longer exists and seems unlikely to return. That’s going nowhere. Sooner or later we should adjust the law to address the emerging reality.