Operation Hardtack was a series of nuclear tests conducted by the United States in 1958. It took place in the Pacific Ocean, primarily at the Marshall Islands, and included a total of 35 tests. The operation aimed to develop and improve nuclear weapons, as well as to study the effects of nuclear explosions. The tests were part of the broader Cold War context, where nations were competing in nuclear capabilities. Operation Hardtack included both atmospheric and underwater detonations, providing valuable data on weapon performance and fallout patterns. The operation significantly contributed to the understanding of nuclear weapons during that era.