To be honest I think our energies are more likely to have to be directed against outside attack, from terrorist Islamists, than from our next-door neighbors. Homeland Security is not going to be successful at fending off attacks forever. There are millions of Muslims out there who are possible terrorist attackers, and as Dr. Rice remarked, we have to be successful at finding and arresting them 100% of the time; they only need to be successful in their efforts once, so more attacks certainly will come.
WELL PUT. And long been a concern of mine.
BTW, in my job at the univ library, I had occasion to be in contact with hispanics who were then--1965-1969--stashing weapons caches away for the day when they would retake the Southwest.
There's PLENTY of hostile forces arouund itching to do satan's work. And SKERRY has been stirring up more of them . . . along with SORELOSER, SCREAMMAN, et al.