World War II saw the beginning of a process of rethinking American immigration and naturalization. The United States had an international image problem to deal with. ‘Removing barriers and debating consequences in the mid-twentieth century’ examines the next phase in US immigration and naturalization policies, a time of revision and relaxation. After the war, Congress was forced to confront a new reality, the massive displacement of people on a scale previously not seen. This had huge moral and political ramifications. Reform efforts culminated in 1965 with the passage of the Immigration and Nationality Act, the most important piece of postwar immigration legislation. Subsequent legislation has veered in different directions, evidence of the complexity of the problem of immigration in the modern world.