the final year of the Truman Administration. Enforcement actions continued to rise under Eisenhower, until reaching a peak of 1.1 million in 1954, the year of Operation Wetback. Enforcement actions then fell by more than 90 percent in 1955, and 1956, and in 1957 were 69,000, the lowest number since 1944. The number of enforcement actions rose again in the 1960s and 1970s, but did not exceed the 1954 peak of Operation Wetback until 1986. At the same time that immigration enforcement was expanding in the late 1940s and early 1950s, the Bracero program was also rapidly expanding legal opportunities for Mexican laborers. Although it began as a wartime measure, the Bracero program saw its largest expansion after the war. The number of wartime braceros peaked at 62,000 in 1944, but the number began to rise again in the late 1940s, and reached its peak in 1956, when the program gave temporary work permits to 445,000 Mexican workers. See also Illegal immigration to the United States Immigration to the United States Operation Gatekeeper Mexican Repatriation Repatriation flight program United States v. Brignoni-Ponce Wetback (slur) Emigration from Mexico References Sources Further reading Copp, Nelson Gage, 'Wetbacks' and Braceros: Mexican Migrant Laborers and American Immigration Policy, 1930–1960. (San Francisco, 1971). García, Juan Ramon. Operation Wetback: The Mass Deportation of Mexican Undocumented Workers in 1954. (Westport CT 1980). Scruggs, Otley M. Braceros, 'Wetbacks', and the Farm Labor Problem: Mexican Agricultural Labor in the United States, 1942–1954. New York 1988. Law enforcement operations in the United States History of immigration to the United States Mexican-American history Presidency of Dwight D. Eisenhower Illegal immigration to the United States Mexico–United States relations Forced migrations in the United States