Contingencies of the early nuclear arms race
S. S. Schweber and Alex Wellerstein
On July 16, 1945, the United States detonated a plutonium-core nuclear weapon in the desert of New Mexico. The test—“Trinity”—was secret, but the Soviet Union was well informed of it through espionage. In August 1945, the United States exploded two nuclear weapons above cities in Japan.
On August 29, 1949, the Soviet Union detonated a plutonium-core nuclear weapon on the steppes of Kazakhstan. The test was secret. Five days later (on September 3), an American B-29 weather plane, on its daily flight between Japan and Alaska to expose radioactive-sensitive filter papers to the air, recorded higher-than-usual levels of radioactivity. This in turn triggered additional probes. By September 19, a group of top-level nuclear scientists had concluded that the detected particles were undoubtedly the traces of an atomic bomb explosion, later dubbed “Joe-1”. On September 23, the news of the Soviet test was announced by President Truman.
Two detonations, two...