Which president made the final decision to use atomic weapons during World War II?

Harry S. Truman made the final decision to use atomic weapons during World War II. Following the death of Franklin D. Roosevelt in April 1945, Truman became president and was briefed on the Manhattan Project, which developed the atomic bomb. The decision to drop atomic bombs on Hiroshima and Nagasaki in August 1945 was influenced by several factors, including the desire to end the war swiftly, minimize American and Allied casualties, and assert U.S. power in the post-war world. Truman believed that using the bomb would bring about a quicker resolution to the conflict with Japan, ultimately leading to a faster end to the fighting. This decision has been debated by historians and ethicists since, but Truman is the president who authorized the use of atomic weapons in an effort to bring World War II to a conclusion.