Not to everybody it wasn't. Some Japanese officers wanted to keep fighting even after two cities were wiped out. (Three if you count the firebombing of Tokyo, which you probably should...)
As proven earlier with Operation Ten-Go / The Battle of the East China Sea, many in the Japanese military preferred spiteful suicidal attacks to surrender, even when the hopelessness of their situation was abundantly clear.
https://en.wikipedia.org/wiki/Bombing_of_Tokyo
https://en.wikipedia.org/wiki/Ky%C5%ABj%C5%8D_incident
As proven earlier with Operation Ten-Go / The Battle of the East China Sea, many in the Japanese military preferred spiteful suicidal attacks to surrender, even when the hopelessness of their situation was abundantly clear.
https://en.wikipedia.org/wiki/Operation_Ten-Go