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Byron York: Could there be another wave of illegal immigration?

MISSION, TX - APRIL 11: U.S. Border Patrol and U.S. Air and Marine agents work together to detain an undocumented immigrant after chasing him down near the U.S.-Mexico border on April 11, 2013 near Mission, Texas. A group of 16 immigrants from Mexico and El Salvador said they crossed the Rio Grande River from Mexico into Texas during the morning hours before they were caught. The Rio Grande Valley sector of has seen more than a 50 percent increase in illegal immigrant crossings from last year, according to the Border Patrol. Agents say they have also seen an additional surge in immigrant traffic since immigration reform negotiations began this year in Washington D.C. Proposed refoms could provide a path to citizenship for many of the estimated 11 million undocumented workers living in the United States. Photo by John Moore/Getty Images) (Photo by John Moore/Getty Images)

One argument often heard in the debate over comprehensive immigration reform is that the flow of illegal immigrants from Mexico to the United States, once measured in the hundreds of thousands per year, has slowed dramatically and is not likely to pick up again.

"All across Mexico's ruddy central plains, most of the people who could go north already have," reported the New York Times in early April. "[P]ast experience and current trends in both Mexico and the United States suggest that legalization would not lead to a sudden flood of illegal immigration on the scale of what occurred after 1986."

Some reformers have cited stories like the Times' to suggest there's no need for sweeping new border security or workplace enforcement measures; illegal immigration is on the decline anyway.

It is true that net migration from Mexico fell to virtually nothing during the depths of the Great Recession. That did not mean Mexicans stopped coming to the U.S., but rather that the number of Mexicans entering the U.S. and the number leaving were about the same. But in the last year or so, there have been signs of an increase, and now a new poll suggests many Mexicans would come to the U.S. if they had the chance. And many of them would come illegally if necessary.

The Pew Research Center's Global Attitudes Project released a survey Monday to help set the stage for President Obama's visit to Mexico later this week. In 1,000 in-person interviews conducted across Mexico last month, Pew researchers asked, in Spanish, "If at this moment, you had the means and opportunity to go to live in the United States, would you go?" Thirty-five percent of those surveyed said yes.

The population of Mexico is about 110 million. If the Pew numbers are correct, that means about 38 million would like to live in the U.S.

Going into a little more detail, Pew found 20 percent of all Mexicans would be "inclined to go work and live in the U.S. without authorization." That's about 22 million people who might come to the U.S. illegally, if they had the chance.

"The story line that we've been hearing that Mexican immigration to the U.S. is now over is simply not true," says Mark Krikorian, head of the Center for Immigration Studies, which favors stricter immigration enforcement. "It could well be that we won't see the same level of Mexican illegal immigration that we saw in the '90s and '00s, but if 38 million people want to come here, that's a lot of people."

The Pew study offers mixed evidence on the magnetic pull of the United States economy for poor Mexicans. On the one hand, Pew asked Mexicans whether people who left their country for the U.S. "have a better life [in the U.S.], a worse life there, or is life neither better nor worse there?" Forty-seven percent of respondents said immigrants to the U.S. had a better life, versus 18 percent who said they had a worse life and 29 percent who said neither. That 47 percent figure is a bit lower than in recent years.

On the other hand, when Pew asked Mexicans whether their friends or relatives who moved to the U.S. had achieved their goals or been disappointed, 70 percent said they had achieved their goals, versus 25 percent who said they had been disappointed.

Finally, Pew found Mexican goodwill toward the United States has risen significantly in the last few years. Favorable attitudes toward the U.S. plunged after the passage of the Arizona immigration law in 2010. At that point, 48 percent of Mexicans said they viewed the U.S. unfavorably, versus 44 percent who viewed the U.S. favorably. Now, the numbers are 66 percent favorable, 30 percent unfavorable.

Put the Pew figures together, and they suggest that large-scale new immigration from Mexico, illegal as well as legal, is entirely possible. Not only are many Mexicans inclined to come to the U.S., but many of the reasons holding them back -- dreadful American economic conditions being the biggest -- could change in the future. Conditions in Mexico could change, too, in a direction that spurs more people to leave.

And that could mean a new wave of illegal immigration. "What it all adds up to is that there are always going to be significant numbers of Mexicans who are going to want to come here, regardless of our laws," says Krikorian. "So border security, and more broadly immigration security, is not something we can dispense with."

Byron York, The Washington Examiner's chief political correspondent, can be contacted at byork@washingtonexaminer.com. His column appears on Tuesday and Friday, and his stories and blog posts appear on washingtonexaminer.com.