There was no conditional surrender possible. The Japanese were still demanding to keep their “colonies” in China and elsewhere. Agreeing to that would be agreeing to continue the Japanese holocaust against the Chinese and the peoples in their other captured territories.
And from the Allied perspective, after the Bataan death march, the massacre of surrendered US troops and civilians in Wake, and the hundreds of similar massacres of surrendered allied troops, and rape and murder of nurses and civilians, across the Pacific, no one was going to allow the Japanese leadership or military off the hook.
Western powers weren’t committing atrocities like the Rape of Nanking during the 30s and 40s. Japanese troops killed surrendered soldiers, raped and murdered civilians not as a rare or exceptional event, but as a standard act in every country they invaded during the 30s and 40s.
And from the Allied perspective, after the Bataan death march, the massacre of surrendered US troops and civilians in Wake, and the hundreds of similar massacres of surrendered allied troops, and rape and murder of nurses and civilians, across the Pacific, no one was going to allow the Japanese leadership or military off the hook.