David Danelo spent three months traveling the 1,952 miles that separate the United States and Mexico--a journey that took him across four states and two countries through a world of rivers and canals, mountains and deserts, highways and dirt roads, fences and border towns. Here the border isn't just an abstraction thrown around in political debates in Washington; it's a physical reality, infinitely more complex than most politicians believe. Danelo's investigative report about a complex, longstanding debate that became a central issue of the 2016 presidential race examines the border in human terms through a cast of colorful characters. As topical today as it was when Danelo made his trek, this revised and updated edition asks and answers the core questions: Should we close the border? Is a fence or wall the answer? Is the U.S. government capable of fully securing the border?