It was the threat of the Allies doing so that moved the emperor to capitulate. Japan didn’t know how many bombs we had and knew this would spell doom for their whole land if they guessed wrong.
One doesn’t have to dish out more than a sample sometimes under the right circumstances.
On the WWII + 70 thread it was interesting to see the headlines. Three big titles:
Soviets Declare War on Japan
Something else (some battle in China?)
And third:
“Atom Bomb Loosed on Nagasaki”
The actual article about the second bomb was fairly small. I thought it interesting. Today we make a big deal out of both of the bombs. Back then, it sounded like it was the “new normal”. Perhaps a bit of psyops going on too.