Yglesias and Labor Economics

Matthew Yglesias showed an economic fallacy today in his comments on "Border Security and Economic Migration". Yglesias repeats the common belief that, if we were to allow more legal migrant workers, the illegal (and mostly Mexican) migration would slowly dry up. Therefore, a "secure border" means we need immigration reform.
http://yglesias.thinkprogress.org/archives/2010/05/border-security-and-economic-migration.php

Well, most likely not. The legal migrants will abide by the minimum wage rules, whereas the illegal immigrant workers have been willing to work below minimum wage. Therefore, the candidates for illegal immigration will not be swayed by the opportunity to come working legally. The ones willing to work below minimum wage will continue to cross the unsecured border to work the illegal jobs.

Immigration reform will not stop people from crossing the dangerous desert. Being a true compassionate humanitarian means stepping up to the plate and accepting the responsibility: By abrogating our responsibility to build a wall across the American Southwest, we have consigned millions of Mexicans to death and deprivation in the desert while they search for a new beginning.