Emperor Hirohito called for Japan to surrender primarily because continued war was leading to inevitable and immense destruction of Japan and its people. His decision was influenced by the devastating impact of the atomic bombings of Hiroshima on August 6 and Nagasaki on August 9, 1945, and the Soviet Union declaring war on Japan. He recognized that further resistance would result in the collapse of the Japanese nation and possibly the extinction of human civilization. Hirohito's surrender speech was intended to end the war and save lives, as well as to preserve the imperial institution by carefully managing Japan's defeat. The surrender was announced by accepting the terms of the Potsdam Declaration, which demanded unconditional surrender, although the emperor never explicitly used the word "surrender" in his speech. His decision was also motivated by a desire to maintain the imperial system to some extent in the postwar period, amidst uncertainty about Japan's future and political stability.