Wrong, you start with the biggest threat.
The number 1 terror threat from illegals is from those who entered the country on a student or tourist visa and then disappeared. They are called sleepers. The primary reason that Congress want to do immigration reform is to reallocate the money being spent to chase Mexicans around the Arisona desert to finding the sleepers. If you followed the student visa tracking fiasco, you'd be sick to your stomach.
The number 2 threat is from Canada, Canada's policies on immigration and political asylum are so lax, it is easy for a bomber to enter there. Once in the country, there is a huge muslim population within which to hide. The Millennium Bomber proves this.
The number 3 threat is the southern border, but it is not from illegals. Congress knows that the increase on border patrol over the last decade, re-enforced after 9-11 has driven up the price that coyotes charge. That price has risen so high that organized crime has taken over the human smuggling. The drug cartel with their international connections and their distribution systems in the US could easily get a terror attack squad into Mexico, across the border, and to their final destination, if the price is right. Immigration reform will eliminate this.
We're talking about stopping illegal aliens AND terrorists, and since a wall would certainly help stop sleeper terrorists from crossing the border as well there's no reason not to build it.
The only immigration reform we need is for the feds to start enforcing the laws they've been ignoring.
Wrong. The USBP and Canadian authorities apprehended a would-be bomber whose target was determined to be LAX terminal on Jan 1, 1999. My family and some friends were scheduled to have flown into LAX that very day. Indeed we did - without incident.
But, when you try to invent reasons beyond the valid reasons, you lose credibility.