Trump likes to say such measures would only last "until we can figure out what is going on" but it's clear what's going on with his campaign. He's not dog-whistling about who's "us" and who's "them," but outright saying so. That "we" are under siege from "them," and that it's high time to raise up the drawbridge and start pouring the burning oil he'll take from the Iraqis down the walls of Fortress America.