Frum defends Arizona's law. He argues that the "true benefit of Arizona’s new law...is not deportation, but deterrence". Echoing a common criticism, he also blames the federal government for not acting:
The experience of the past two years has shown that migration responds swiftly to changing incentives. The Center for Immigration Studies has tracked monthly Census data for young Hispanic males with low levels of education -- a good proxy for the illegal immigrant population. Between the summer of 2007 and the first quarter of 2009, that population actually declined. Extrapolating from survey figures, CIS estimates that the illegal population in the U.S. dropped by1.7 million during the recession. The number of illegals entering the country fell by about one-third while the number returning home doubled .
States and counties that have strengthened enforcement have seen declines in the population of non-English-speaking students in local schools (another good proxy for the illegal immigrant population).
Arizona’s law seeks a similar effect.