Corley said "it's not easy to retrain people," and that "the further you get away from your education the less knowledge you have of the new technologies, and technology is always moving forward."
The Economic Policy Institute has found that guest workers are mostly young and provide competition to new U.S. graduates and provide companies "a large supply of younger, lower-paid workers who can substitute for older workers." The institute says the large supply of guest workers has kept IT wages flat.
Demetrios Papademetriou, executive director of the Migration Policy Institute, an independent, non-partisan think tank, agrees that immigration can increase IT employment numbers.
In an interview, Papademetriou said that the literature on this issue "has become comfortable with a consensus that basically says that high-end immigration produces more jobs than it takes." However, he didn't put a number on the number of jobs created.
Employers that use H-1B visa workers are not obligated to first try to fill the job with a U.S. worker, either a citizen or permanent resident.
Ron Hira, a public policy professor at the Rochester Institute of Technology and researcher of tech immigration issues, said that most studies try to measure the impact of immigrants on the wages of Americans rather than number of jobs for Americans. Some analysts find negative impacts, others neutral or positive, he said.
"The upshot is that economists say that H-1B workers who complement the skills and capabilities of American workers increase the wages for those Americans," said Hira. "H-1B workers who substitute for the skills and capabilities of American workers lower wages for those Americans."
H-1B workers at the large offshore firms "are mostly substituting for Americans," said Hira. Only NASSCOM, the Indian trade group, "has had the gumption to claim that offshore outsourcing firms are doing good for America," he said. But that trade group's principal argument is that it helps America by making its customers more efficient, said Hira.
It "has rarely argued that their firms create jobs for Americans," he said.
Patrick Thibodeau covers cloud computing and enterprise applications, outsourcing, government IT policies, data centers and IT workforce issues for Computerworld. Follow Patrick on Twitter at @DCgov or subscribe to Patrick's RSS feed. His e-mail address is email@example.com.
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