U.S. President Donald Trump wants to build a wall along the U.S.-Mexican border. Several of his predecessors sought to foster inter-American harmony by building roads instead. The result was the Pan-American Highway, whose 30,000 miles link Alaska to Tierra del Fuego, at the southern tip of South America. As Rutkow shows in this history of the highway, the various justifications for building the road included promoting automobile exports, fortifying antifascist defenses during the 1930s and 1940s, and advancing economic and social development in Latin America. Rutkow does an excellent job linking the domestic politics and economies of the countries along the highway to the international diplomacy that made it possible. Well-known American leaders, including Henry Clay, Andrew Carnegie, and George Marshall, have colorful cameos. As Rutkow shows, some Latin American countries, most notably Argentina, saw the project as a Trojan horse for U.S. imperialism. Unfortunately, Rutkow does not examine this history in detail, as his coverage of South America is far less complete than his impressive research on Mexico and Central America.