evidence: After the Imperial Japanese Navy Air Service attack on Pearl Harbor, American policy makers tried to persuade the Soviet Union to join them in the fight against Japan. Cordell Hull, the American Secretary of State, met with the Soviet Ambassador, Maxim Litvinov, a few days after the Pearl Harbor incident. According to reliable sources, he said, ‘Japan, notwithstanding the terms of the Russo-Japanese agreement, was under the strictest commitment to Germany to attack Russia and any other country fighting against Germany whenever Hitler demanded’ (The memoirs of Cordell Hull). [...] However, on 8 August 1945, two days after the atomic bombing of Hiroshima and the day before the second bomb fell on Nagasaki, the Soviet Union declared war on Japan. The news of impending war with the Soviet Union sent shockwaves through Japanese policy makers: just before he left Moscow for the Conference, Stalin had received a personal message from the Japanese Emperor, asking him to act as intermediary between Japan and the United States. The Soviet betrayal was an important factor in forcing Japan to surrender. [...] At 10:00 on 14 August 1945, as the situation deteriorated, the Emperor declared before his cabinet at the Imperial conference: ‘The military situation has changed suddenly. The Soviet Union entered the war against us. Suicide attacks can’t compete with the power of science. Therefore, there is no alternative but to accept the Potsdam terms.’