Final answer:
The U.S. government's effort to build the atomic bomb was called the Manhattan Project.
Step-by-step explanation:
The U.S. government's effort to build the atomic bomb was called:
The Manhattan Project.
The Manhattan Project was a top-secret research project during World War II that aimed to develop the first atomic bombs. It was led by the United States with support from the United Kingdom and Canada. The project successfully resulted in the creation of two atomic bombs, which were later dropped on the Japanese cities of Hiroshima and Nagasaki.
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