No, the first nuclear weapon was not the atomic bomb. The first nuclear weapon was actually the "Trinity" test detonation, which took place on July 16, 1945, in New Mexico, United States. This test was the culmination of the Manhattan Project, a research and development program during World War II that aimed to develop atomic weapons. The atomic bomb was subsequently used in warfare when the United States dropped two atomic bombs on the Japanese cities of Hiroshima and Nagasaki in August 1945.
