We're sharing an episode from our friends at Latino USA! In this episode, producer Reynaldo Leaños Jr. travels to southern Arizona where one of the first major concentrations of surveillance towers on the southern border were built, and he looks at what these towers mean today, and for the future of those crossing, and living, there.

The "virtual wall" across the U.S.-Mexico border is made up of things like drones, sensors, cameras and… surveillance towers. Both Democrats and Republicans have supported border technology through the years, but advocates and researchers argue that a virtual wall can be as controversial, and deadly, as a physical wall.