Enrico Fermi first achieved self-sustaining nuclear fission in Chicago in 1942. In 1946, the Atomic Energy Commission was established to oversee research into peaceful applications for the technology. The first experimental breeder reactor went live in Arco, Idaho (1951), with the first commercial plant following at Shippingport, Pennsylvania (1957). The Price-Anderson Act (1957) offered financial sureties to civilian populations and contractors in the event of accident, ushering in a period of steady proliferation. It also saw the birth of the anti-nuclear movement, forcing the abandonment of plans for a plant near San Francisco. By 1971, there were 22 operational plants producing 2.4 per cent of US electricity; by 1984, nuclear power had overtaken hydropower and gas, to produce 14 per cent of US electricity. Mounting concerns regarding safety and waste disposal were dramatically exacerbated by the Three Mile Island accident (1979), resulting in a decline in the commissioning of new reactors.
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