Think Again: Immigration - By Shannon O'Neil

"Mexicans Will Keep Flooding the United States If Allowed."

Not likely. Starting in 2005, the number of migrants coming from Mexico -- who comprise one-third of the U.S. foreign born population -- began declining. The deceleration then picked up pace with the 2008 world financial crisis, so much so that a 2012 Pew Hispanic report noted that for the first time in decades, the number of Mexicans entering the country was the same as those leaving -- leading to a "net zero" in terms of flows.

Though the U.S. recession played a role, perhaps the most important -- and permanent -- factor behind this shift is demographic. In the 1970s, even as mortality rates declined, Mexican women on average had seven children. Today, that number is much closer to two -- much like the United States. This means that the "extra" Mexican youth who came of age in the 1990s and early 2000s have dissipated, and are unlikely to return again. These fewer siblings are staying in school longer -- most now through high school and many into college -- further reducing the pool of young men and women searching for opportunities to the north.

Economic prospects at home have also improved. The booms and busts of the 1980s and 1990s, which pushed so many Mexicans across the border, seem to have ended. Instead, Mexico's new economic story is one of a growing middle class -- now some 60 million strong -- made up of lawyers, accountants, small and medium size business owners, higher-skilled factory workers, and taxi drivers, among many other professions. These economic shifts also have encouraged Mexicans to stay home.

This is not to say that immigration from Mexico will dry up completely. The combination of better pay and rising U.S. demand for labor will continue to draw many from Mexico -- as well as from around the world -- to America's workplaces. For instance, immigration from Central America -- though much lower in terms of sheer numbers -- continues unabated. And immigration reform, which is now on the table after the Republican Party's record-low showing with Hispanic voters, could make it easier for many to stay, and for more to come. 

Still, even if new legislation opens the door to citizenship, history suggests that all of these immigrants wouldn't rush in. In the 26 years since Congress passed the Immigration Reform and Control Act, which created a pathway for legalization, fewer than a third of the 2.7 million Mexicans eligible under the law decided to naturalize.

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