Operation Crossroads
There were only seven nuclear bombs in existence in July 1946. The two bombs used in the test were Fat Man plutonium implosion-type nuclear weapons of the kind dropped on Nagasaki. The "Able" bomb was stenciled with the name "Gilda" and decorated with an "Esquire" magazine photograph of Rita Hayworth, star of the 1946 movie, "Gilda". The "Baker" bomb was "Helen of Bikini." This femme-fatale theme for nuclear weapons, combining seduction and destruction, is epitomized by the use in all languages, starting in 1946, of "bikini" as the name for a woman's two-piece bathing suit.
Military history of the United States during World War II
As victory for the United States slowly approached, casualties mounted. A fear in the American high command was that an invasion of mainland Japan would lead to enormous losses on the part of the Allies, as casualty estimates for the planned Operation Downfall demonstrate. As Japan was able to withstood the devastating incendiary raids and the naval blockade despite hundreds of thousands of civilian deaths, President Harry Truman gave the order to drop the two only-available atomic bombs, hoping that such sheer force of destruction on a city would break Japanese resolve and end the war. The first bomb was dropped on an industrial city, Hiroshima, on 6 August 1945, killing appropriately 70,000 people. A second bomb was dropped on another industrial city, Nagasaki, on 9 August after it appeared that the Japanese high command was not planning to surrender, killing approximately 35,000 people. Fearing additional atomic attacks, Japan surrendered on 15 August 1945.