About 2,000 American Citizens were killed in the bombing of Hiroshima

Detailed reports of the unprecedented scale of the destruction at Hiroshima were received in Tokyo, but two days passed before the government met to consider the changed situation. At 04:00 on August 9, word reached Tokyo that the Soviet Union had broken the Neutrality Pact, declared war on Japan and launched an invasion of Manchuria.

These "twin shocks"—the atomic bombing of Hiroshima and the Soviet entry—had immediate profound effects on Prime Minister Suzuki and Foreign Minister Tōgō Shigenori, who concurred that the government must end the war at once. However, the senior leadership of the Japanese Army took the news in stride, grossly underestimating the scale of the attack. They did start preparations to impose martial law on the nation, with the support of Minister of War Anami, to stop anyone attempting to make peace. Hirohito told Kido to "quickly control the situation" because "the Soviet Union has declared war and today began hostilities against us."

The Supreme Council met at 10:30. Suzuki, who had just come from a meeting with the Emperor, said it was impossible to continue the war. Tōgō Shigenori said that they could accept the terms of the Potsdam Declaration, but they needed a guarantee of the Emperor's position. Navy Minister Yonai said that they had to make some diplomatic proposal—they could no longer afford to wait for better circumstances.

In the middle of the meeting, shortly after 11:00, news arrived that Nagasaki, on the west coast of Kyūshū, had been hit by a second atomic bomb (called "Fat Man" by the Americans). By the time the meeting ended, the Big Six had split 3–3. Suzuki, Tōgō, and Admiral Yonai favored Tōgō's one additional condition to Potsdam, while Generals Anami, Umezu, and Admiral Toyoda insisted on three further terms that modified Potsdam: that Japan handle her own disarmament, that Japan deal with any Japanese war criminals, and that there be no occupation of Japan.

"...in 1945... Secretary of War Stimson, visiting my headquarters in Germany, informed me that our government was preparing to drop an atomic bomb on Japan. I was one of those who felt that there were a number of cogent reasons to question the wisdom of such an act. ...the Secretary, upon giving me the news of the successful bomb test in New Mexico, and of the plan for using it, asked for my reaction, apparently expecting a vigorous assent.

"During his recitation of the relevant facts, I had been conscious of a feeling of depression and so I voiced to him my grave misgivings, first on the basis of my belief that Japan was already defeated and that dropping the bomb was completely unnecessary, and secondly because I thought that our country should avoid shocking world opinion by the use of a weapon whose employment was, I thought, no longer mandatory as a measure to save American lives. It was my belief that Japan was, at that very moment, seeking some way to surrender with a minimum loss of 'face'. The Secretary was deeply perturbed by my attitude..."

- Dwight Eisenhower, Mandate For Change, pg. 380

For example, an April 30, 1946 study by the War Department's Military Intelligence Division concluded, "The war would almost certainly have terminated when Russia entered the war against Japan."<3>