Hirohito cited the Soviet Union’s entry into the war in his August 17, 1945 speech to Japan’s military.
Two days after his public surrender broadcast, Hirohito addressed officers and men of the imperial forces in a separate message. In that speech, he said that the Soviet Union had entered the war against Japan and that continuing the conflict would endanger the foundations of the Japanese Empire.
The Soviet Union declared war on Japan on August 8, 1945, and Soviet forces invaded Japanese-held territory in Manchuria beginning the next day. This development came between the atomic bombing of Hiroshima on August 6 and the bombing of Nagasaki on August 9. Japan’s leaders therefore faced rapidly worsening military and diplomatic circumstances.
Hirohito’s public speech emphasized the destructive power of the atomic bomb, while his military speech highlighted the Soviet entry into the conflict. The difference reflects the separate audiences and the government’s effort to explain surrender to civilians and the armed forces.