Of course we didn’t have any more A Bombs ready to go after Nagasaki, but they didn’t know it.
All they could imagine was every City in Japan reduced to ashes one A Bomb at a time.
Even then, Tojo’s Military was denying the inevitable.
Apparently we did.
https://www.thedailybeast.com/us-planned-to-drop-12-atomic-bombs-on-japan