There was plenty of evidence from Okinawa, Iwo Jima etc to indicate that Japan would fight to the last man, woman and child, and the plans for a land invasion of Japan assumed body counts that were horrific even by WW2 standards:
That said, this doesn't really excuse dropping not one but two bombs on civilian centers. Dropping one a stone's throw from Tokyo (say, the Boso or Izu peninsulas) would likely have made the point as effectively and with less casualties.
https://en.wikipedia.org/wiki/Operation_Downfall
That said, this doesn't really excuse dropping not one but two bombs on civilian centers. Dropping one a stone's throw from Tokyo (say, the Boso or Izu peninsulas) would likely have made the point as effectively and with less casualties.