In the 3/11/13 issue of the WSJ, a former ambassador to Canada and a former diplomat to Mexico reproduce essentially most of the argument Sergei Nikiforov and I made clearly more than three years ago:
The solution to the problem of illegal immigration involves separating legal residency from citizenship.
The argument was developed in a 2009 issue of the libertarian Independent Review under the title: “If Mexicans and Americans Could Cross the Border Freely.”
The article is linked to this blog.
I also wish to repeat what I have already said recently on this blog: There is not much demand for US citizenship among illegal immigrants. The demand comes almost entirely from cynical professional members of the Democratic Party.