We drove 2,428 miles on both sides of the U.S.-Mexico border, and it's safe to say that for much of the road trip, we were being watched.
Border Patrol agents, customs officers, cameras, sensors, radar and aircraft track movement in the Borderland. None of that has stopped the struggle to control the border, or the debate over how best to do it.
The Border Patrol — part of U.S. Customs and Border Protection — allowed us a look inside the communications center at its headquarters in Laredo, Texas. The room had no windows, just a giant wall of screens.