Despite such setbacks, the militarists who dominated the Japanese government rejected any suggestions of surrender.

End of the War in the Pacific

With war won in Europe, the Allies poured their resources into defeating Japan. By mid-1945, most of the Japanese navy and air force had been destroyed. Yet the Japanese still had an army of two million men. The road to victory, it appeared, would be long and costly.

Japanese Resistance

As American forces closed in on Japan, the Japanese put up fierce resistance. By 1944, young Japanese kamikaze (kah muh KAH zee) pilots were undertaking suicide missions, crashing their explosive-laden airplanes into American warships.

Kamikaze attacks were a desperate attempt to ward off American advances. Japanese pilots crashed into Allied aircraft carriers and other ships, killing American sailors along with themselves.

The next year, in bloody battles on the islands of Iwo Jima from February to March 1945 and Okinawa from April to July 1945, Japanese forces showed that they would fight to the death rather than surrender. Some American officials estimated that an invasion of Japan would cost a million or more casualties.

A Powerful New Weapon

While Allied military leaders planned for invasion, scientists offered another way to end the war. Since the early 1900s, scientists had understood that matter, made up of atoms, could be converted into pure energy. In military terms, this meant that by splitting the atom, scientists could create an explosion far more powerful than any yet known.

During the war, Allied scientists—some of them German and Italian refugees—raced to harness the atom before the Germans could. In July 1945, the top secret Manhattan Project, successfully tested the first atomic bomb at Alamogordo, New Mexico.

News of this test was brought to the new American president, Harry Truman. He realized that the atomic bomb was a terrible new force for destruction. Still, after consulting with his advisors, he decided to use the new weapon against Japan. Truman believed that dropping the atomic bomb would bring the war to a faster end and save American lives.

President Harry S. Truman and U.S. Secretary of State James Byrne examine a map of Europe aboard the U.S.S. Augusta on their way to the “big three” conference in Potsdam in the summer of 1945.

At the time, Truman was meeting with other Allied leaders in the city of Potsdam, Germany. They issued a warning to Japan to surrender or face “complete destruction” and “utter devastation.” When the Japanese ignored the warning, the United States took action.

Table of Contents