Your comment about Tancredo is ridiculous and frustrating. To base the argument that illegal immigration doesn't have anything to do with terrorism nor can it could be likened to saying on Sept. 10th that there was no danger of being attacked by people who were here on visas. Just because it hasn't happened yet doesn't mean it isn't a legitimate danger. I expect more logical reasoning from someone who is going to be published for other people to spend (and at this point waste) their time reading.
Fact: many Yemenis and other Middle Easterners (including Iraqis) have been detained at the Mexican/US border.
Fact: the terrorists just apprehended for trying to attack an Army base in Arizona hired Mexican drug cartels to bring them into the US.
The conclusion is obvious: at the least, this is a serious potential danger, if not an immanent danger.