That’s the Soviet explanation to Japan, but the Soviets were already committed to going to war against Japan as part of a long-standing agreement with the other Allies that the USSR would attack Japan after Germany was defeated.
Sure, it was the matter of discussion since Tehrain conference. Yet in 1943 it were clear the USSR should join the war against Japane. The Japane knew this via the German intelligence service, but i heard the Japanese still hoped for possible the Soviet/Allies hostilities to avoid the total war against Japane.
If you read John Toland’s The Rising Sun, written pretty much from the Japanese perspective, you will see just how peculiarly messed up the Japanese direction of the war was and how woefully cumbersome their decision making process was. While the Japanese were quite successful at first when they launched their initial surprise attacks - surprise attacks are often successful against essentially unprepared and fairly helpless enemies (witness Hitler’s Barbarossa) - they were spectacularly unsuccessful in the follow up. Consider that within 6 months of Pearl Harbor 1) the thrust to Australia had been stopped in the Coral Sea and 2) the offensive power of the IJN had been crippled at Mdway. It was all downhill from there. It took a long time to defeat the Japanese because of the tenacious and suicidal fighting spirit of their troops where personal death was honorable and held in high regard, whereas the Americans, Aussies and British preferred to be alive after the battle. But all this resulted in was the senseless deaths of millions of Japanese to no good purpose.
Which makes it all the more curious why the Japanese tried to negotiate a peace in mid-1945 through the Soviets when Japan knew that the USSR was about to, or at least likely to, attack it.
Perhaps this is just another example of Japan’s failure to understand the other side’s attitudes and likely responses to Japan’s actions, as with Pearl Harbor.
“Unrealistic” and prone to fantastic schemes to avoid certain defeat characterized Japan’s deliberations throughout the war. Japan was defeated the moment it attacked Pearl Harbor - they could have saved themselves a lot of trouble, lives and cities by not underestimating the allies before they attacked. As I mentioned earlier, their planning on a strategic level was terrible. Japan’s ambassador to Russia had taken the measure of the Russians and knew how intractable they were and how unlikely they were to listen to Japanese proposals. His bosses in Tokyo paid no attention to his warnings.
They had “never” lost a war before. Defeat was inconcievable. The shame of it was unbearable. It took the emperor to tell them to “bear the unbearable”.