Immigration and Terrorism
The linkage is absurd for two different reasons. The first is that current illegal immigrants are not Muslims and have no connection with or allegiance to Islamic organizations, terrorist or otherwise. Most of them are Catholics. They are no more likely to support Islamic terrorism than the people already here—probably less likely.
The second is that the U.S. doesn't control its borders, isn't going to control its borders, and probably cannot at any acceptable cost control its borders, in the sense relevant to the terrorist issue. In 2004, the most recent year for which I found figures, there were more than eighty million tourist arrivals in North America, presumably most of them in the U.S. Anyone with sufficient resources and ability to pose a serious terrorist threat can get into the country as one of those tens of millions—he doesn't have to scramble through a tunnel under the U.S./Mexican border. And making it a criminal offense to hire illegal aliens will have very little effect on those aliens who are working for al-Qaeda. They already have a job.
There are, of course, many other arguments pro and con on the subject of immigration, a subject I may return to in a later post. But this one isn't an argument, it's pure demagoguery.
My own view of the subject is best summed up in an old Buffy Sainte Marie song:
Welcome, welcome, Immigrante,
To my country welcome home.