Oops. Census figures on the number of illegal immigrants in the US may be way off.
Instead of the official estimate of 6 million, researchers now say the number may be closer to 9 million to 11 million. That would amount to some 3 to 4 percent of the US population. And most are Mexicans who can hide out in Hispanic enclaves of Southwestern cities, eluding a head count.
Tracking illegal migration is almost as difficult as tracking US opinion on this topic. Americans blow hot and cold on immigration. If jobs are plentiful, support grows. But if the economy falters, as it now has, they want tighter borders. For low-income Americans especially, illegal workers are resented for taking away jobs.
The latest opinion poll, done by this newspaper, shows that 41 percent of Americans favor reducing immigration, while 33 percent prefer current levels (see story on page 3). Last fall, just before the economy slipped, the numbers were roughly reversed, according to a similar poll by Gallup.
Congress watches these polls closely as it continually weighs new immigration measures. The latest bill on the table would permit hundreds of thousands of Mexicans to enter the US each year to work on a temporary basis. Such a measure recognizes that Mexican migration is unlike any previous migration to the US.
US patrols and wire fences just aren't enough to stem the flow of people across a 2,000-mile land border from a third-world country of 100 million to a first-world nation of 284 million - especially when the income gap is 7 to 1.
Maybe with a controlled program of "guest workers," more would-be Mexican migrants would line up at the US Embassy and not at the border.
What's remarkable about Mexican migration is the sheer numbers, its persistence over decades, the long-time concentration of illegal workers in a few areas, and the slow assimilation. Immigrants from Europe and Asia have never been like that.
Naturalization rates for Mexicans are relatively low, and the rate of intermarriage between Hispanics and other Americans has declined. About one-quarter of all Mexican immigrants haven't learned English.
Such numbers only punch a larger hole in the myth that the US has been a quick melting pot of ethnic peoples. But still, the large size and the unique style of Mexican immigration challenges the cultural and political balance of the United States.
That's partly why Washington gave a polite "no, thank you" to a proposal by Mexican President Vicente Fox to open the border for workers. (Mexico itself deported 160,000 undocumented migrants last year.)
Mexican immigrants serve many economic purposes, but the illegal kind in particular challenges the national identity and the nation's laws. Immigration controls only go so far. Uplifting Mexico's economy is the best solution, but that may take decades.
In the meantime, public opinion will fluctuate and Congress will continue to try to find more answers.
(c) Copyright 2001. The Christian Science Monitor