Nogales, Arizona, and Nogales, Sonora, are known as “Ambos Nogales” — “both Nogaleses.” The city straddles the border of Arizona and Sonora, Mexico. For a long time, a hole-riddled chain-link fence ran along that border. Residents could cross back and forth with ease. But in 1995, the federal government replaced the chain-link fence with a wall. Over time, that wall has been fortified with surveillance towers, more Customs and Border Patrol agents, and drones.  President Trump wants to extend the Nogales model all along the US-Mexico border. In the final episode of the season, The Impact goes to Nogales with the Arizona Republic to find out why the federal government decided to build the wall, how it has changed Ambos Nogales, and how it has affected migrants who hope to cross into the United States. Further listening and reading:  Rafael Carranza’s reporting in the Arizona Republic Maritza Dominguez’s work on the Valley 101 podcast  Radiolab’s Border Trilogy explores Operation Blockade and the federal government’s Prevention Through Deterrence policy Vox’s guide to where 2020 candidates stand on policy, including immigration Subscribe to The Impact on Apple Podcasts, Spotify, or your favorite podcast app to automatically get new episodes of the latest season each week. Host: Jillian Weinberger, @jbweinz About Vox: Vox is a news network that helps you cut through the noise and understand what's really driving the events in the headlines. Learn more about your ad choices. Visit podcastchoices.com/adchoices