Why did President Truman order the use of the atomic bomd on japan?

Truman believed that using the Atomic Bomb would save American lives. If the Allies had to invade Japan, the Japanese would have used everything in their power to repel the invasion. Going from island to island would cost a high toll in American deaths. Truman also considered the brutality that the Japanese had inflicted upon American prisoners of war. Truman said “The only language they seem to understand is one we have been using. . .” military force. He also considered the use of the Bomb as retaliation for Pearl Harbor. The use of the bomb was also seen as a bargaining chip in postwar negotiations with the Soviets. They would be impressed with the power the US now possessed and Truman believed he could get concessions out of Stalin.