What was the rational given as a justification to use the atomic bomb against Japan?

The primary justification for using the atomic bomb against Japan was to expedite the end of World War II and save lives. U.S. leaders believed that a conventional invasion of Japan would result in significant casualties for both American forces and Japanese civilians. Additionally, demonstrating the bomb's power was seen as a means to strengthen the U.S. position in post-war negotiations, particularly with the Soviet Union. Ultimately, the decision was framed as a way to bring about a swift conclusion to the war and avoid further suffering.