Support. If someone out there is going to smuggle a nuke (RDD/Anthrax/etc) into the United States, they'll land it in Mexico and give a coyote $500 to take it over the border. They're not going to spend seven billion dollars for the right to manage operations at a number of places guarded by DHS.
I couldn't help but chuckle at your post; not in a mocking way but in how dead on it is.