Travelers on Interstate 19 don’t need any “Welcome to Mexico” signs to know that the border is near.

Twenty-five miles north of the line, a giant white canopy stretches over the northbound lanes, with green-shirted border patrol agents and drug-sniffing dogs buzzing around the checkpoint. Farther south in Nogales, Ariz., green-and-white border patrol vehicles are as conspicuous as yellow cabs in New York, and stadium lights trained on the border fence dwarf the rustic Sonoran homes below….

via Is US-Mexico border secure enough? Immigration reform could hinge on answer. – CSMonitor.com.