Nations rapidly industrialized after World War II, sharply increasing the extraction of resources from the natural world. Colonial empires broke up on land after the war, but they were re-created in the oceans. The United States, Japan, and the Soviet Union, as well as the British, Germans, and Spanish, industrialized their fisheries, replacing fleets of small-scale, independent artisanal fishermen with fewer but much larger government-subsidized ships. Nations like South Korea and China, as well as the Eastern Bloc countries of Poland and Bulgaria, also began fishing on an almost unimaginable scale. Countries raced to find new stocks of fish to exploit. As the Cold War deepened, nations sought to negotiate fishery agreements with Third World nations. The conflict over territorial claims led to the development of the Law of the Sea process, starting in 1958, and to the adoption of 200-mile exclusive economic zones (EEZ) in the 1970s.
Fishing expanded with the understanding that fish stocks were robust and could withstand high harvest rates. The adoption of maximum sustained yield (MSY) after 1954 as the goal of postwar fishery negotiations assumed that fish had surplus and that scientists could determine how many fish could safely be caught. As fish stocks faltered under the onslaught of industrial fisheries, scientists re-assessed their assumptions about how many fish could be caught, but MSY, although modified, continues to be at the heart of modern fisheries management.