Potsdam Declaration Deliberation at the Foreign Ministry

Following the issuance of the Potsdam Declaration by the United States, United Kingdom, and China on July 26, 1945, the Foreign Ministry's radio monitoring room was, together with the Domei News Agency and Army and Navy receiving stations, among the first to receive the broadcast, early on the morning of 27 July (Japan time). Ministry officials in the Treaty Bureau undertook the critical translation and legal analysis of the declaration's terms; Japanese Wikipedia names Shimoda Takeso, chief of the bureau's First Section, as the translator. A meeting of senior ministry officials concluded that the declaration in substance offered a conditional peace and decided that it should be published without official comment.

At the Supreme War Council and the cabinet on 27 July, Foreign Minister Shigenori Togo argued that the declaration was an offer of peace on conditions and that rejecting it would have extremely grave consequences, and urged that no position be taken until the Soviet response to Japan's request for mediation was known. On 28 July, however, the newspapers carried the text with dismissive comment, and the military demanded an explicit rejection. At a press conference that day Prime Minister Suzuki Kantaro said the government would 'mokusatsu' the declaration and fight the war through; relayed abroad by Domei, the controversial statement was understood by the Allies as a rejection.

The atomic bombings of Hiroshima (6 August) and Nagasaki (9 August) and the Soviet entry into the war on 9 August transformed the situation. At the Imperial Conference held from late on 9 August into the early hours of 10 August, Togo's proposal to accept on the sole condition of preserving the national polity was deadlocked against the view of Army Minister Anami Korechika and others who wanted further conditions, until the Emperor decided in favour of the Foreign Minister's proposal. On the morning of 10 August the ministry sent the acceptance, with the understanding that it did not prejudice the prerogatives of the Emperor as sovereign ruler, through neutral Switzerland and Sweden. The reply of US Secretary of State Byrnes, received on 12 August, stated that the authority of the Emperor and the government would be 'subject to' the Supreme Commander; the ministry translated this as 'placed under the restriction of', while the Army read it as subordination and called for a further inquiry, reopening the dispute.

The deliberations over the Japanese response continued until the Imperial decision to accept at the conference of August 14, 1945. That day the ministry notified the Allies through Minister Kase Shunichi in Bern and Minister Okamoto Suemasa in Stockholm; the Emperor's rescript was broadcast at noon on 15 August, and on 2 September Togo's successor Shigemitsu Mamoru and Chief of the Army General Staff Umezu Yoshijiro signed the Instrument of Surrender aboard USS Missouri in Tokyo Bay. Togo is generally regarded as the leading voice within the cabinet for acceptance, recognising that the declaration offered the best terms Japan could hope for. After the war he was sentenced to 20 years' imprisonment by the International Military Tribunal for the Far East and died in custody in 1950.