Why the Immigration Issue May Just Fade Away

The U.S.-Mexico border fence near Campo, Calif. David McNew / Getty Images

Yet again, Americans are suffering a period of national distress over illegal immigration. The latest episode started when an Arizona rancher was killed near the Mexican border in March—perhaps by an immigrant, though investigators still aren't sure. Residents in the area loaded up on guns and ammo. As Bill O'Reilly fumed about the "invasion" of illegal aliens from Mexico, officials pleaded for the government to dispatch National Guard troops to the border. The following month, Arizona passed the most stringent immigration law in the land, sending tens of thousands of protesters into the streets around the country. Congressional lawmakers are now pledging to take another crack at comprehensive immigration reform, and the White House last week decided to send in as many as 1,200 National Guard troops. Critics like Arizona Sen. John McCain say that's not nearly enough.

Yet all this angst may be an over-reaction. A little-known, but enormously significant, demographic development has been unfolding south of our border. The fertility rate in Mexico—whose emigrants account for a majority of the United States' undocumented population—has undergone one of the steepest declines in history, from about 6.7 children per woman in 1970 to about 2.1 today, according to World Bank figures. That makes it roughly equal to the U.S. rate and puts it at what demographers call "replacement level," the point at which women are having just enough babies to sustain the current population. In coming years it's expected to dip even further. Other countries in Latin America have experienced a similar drop, though not as sharp. All of which means that the ranks of those "invading" hordes are thinning—rapidly.

The flow of undocumented immigrants began to taper in the middle of the past decade. According to the Pew Hispanic Center, the influx averaged 800,000 per year from 2000 to 2004, then dropped to about 500,000 per year from 2005 to 2008. It has almost certainly decreased even more since then, as the Great Recession has wiped out demand for foreign labor. People think of the torrent of illegal immigration in the recent past, and "it scares the pants off them," says Dowell Myers, a professor in the School of Policy, Planning, and Development at the University of Southern California. But "the [demographic] trends that were driving changes in the last decade won't be there in the next decade."

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Mexico's fertility rate has plummeted for a variety of reasons. Starting in the 1970s, its government undertook one of the most aggressive contraception campaigns in Latin America and set up family-planning clinics across the country. Women also received better schooling, and as Mexico continued to urbanize and industrialize they entered the workforce in much higher numbers. The result was more economic opportunity, greater control over their lives—and fewer babies.

When women start having fewer kids, that means fewer individuals will be entering the labor force two decades later. It has taken longer for that effect to appear in Mexico, however, because even though the fertility rate began falling in the late 1970s, the number of women of childbearing age kept growing. As a result, the pool of newly minted Mexican workers has continued to swell through today. But that's about to change. As soon as next year, demographers say, the number of new entrants into the Mexican labor force is expected to start decreasing. This year that figure is about 750,000, says Félix Vélez, secretary-general of Mexico's National Population Council. By 2020 it's expected to drop to 600,000, and by 2030 to 300,000.

Right now the Mexican economy can't absorb its new workers. In an average year the country produces 400,000 to 500,000 new jobs, says Vélez. But over time the figures should reach equilibrium. How soon that happens depends in part on Mexico's ability to generate respectable growth. The government enacted a number of reforms in recent decades, like lowering trade barriers and privatizing industries. But, says James Gerber, an economics professor at San Diego State University, it needs to do more: dismantle oligopolies, beef up tax collection, increase oil production—all of which he thinks is possible. Combine a solid economy with a labor force that gains fewer workers each year, and the pressure to emigrate is likely to wane.

Of course, many Mexicans will continue to feel the urge to move north regardless of economic changes. Over many decades, migration has become ingrained in the culture. Jeffrey Passel, senior demographer at the Pew Hispanic Center, recalls visiting a school where every kid in the class had an uncle in the U.S. and most planned to move there. "I think we're going to continue to see migration," he says. In all likelihood, however, it won't be nearly as overwhelming as the deluge of the 1990s and early 2000s.

Many Americans don't realize just how unusual that deluge was. History, economics, and demographics conspired to create a perfect storm, says Gordon Hanson, an economics professor at the University of California, San Diego, who has studied the issue in depth. In the 1960s, he explains, the baby boom ended in the U.S., but it continued for another two decades in Mexico. So in the 1980s and 1990s, there were fewer new U.S. workers looking for jobs but more Mexicans. On top of that, in 1982 the Mexican economy suffered a debt crisis, followed by nearly two decades of sluggish growth. The American economy, on the other hand, performed far better, especially in the mid to late 1990s, when it was humming at full throttle and hungry for foreign labor. "If you look back at the last two to three decades, it was really an exceptional period," says Hanson.

In the coming years, the politics of immigration could be completely scrambled: Mexican migration will taper off further just as baby boomers begin retiring in 2012. USC's Myers predicts that the American labor force will start shrinking in some parts of the country by 2015, and that as boomers reach old age they'll create even more demand for workers: "I wouldn't be surprised if Arizona starts pleading for Mexican workers who can help them in their retirement homes," he says. "The potential here is to totally reverse our attitudes toward Mexican immigration." It's hard to imagine right now, but if the numbers hold up, the crisis on our borders may end up abating on its own.