And even after dropping 2 nukes, and believing the US had 100 more, it took days more, and some additional attacks, to convince Japan to surrender. And even after all this, there was a serious attempted coup.
[1] https://en.m.wikipedia.org/wiki/Surrender_of_Japan#:~:text=T....
Some more color, from Wikipedia:
"The Japanese cabinet considered the Allied response, and Suzuki argued that they must reject it and insist on an explicit guarantee for the imperial system. Anami returned to his position that there be no occupation of Japan. Afterward, Tōgō told Suzuki that there was no hope of getting better terms, and Kido conveyed the Emperor's will that Japan surrender. [...]
That day, Hirohito informed the imperial family of his decision to surrender. One of his uncles, Prince Asaka, then asked whether the war would be continued if the kokutai (imperial sovereignty) could not be preserved. The Emperor simply replied "of course.""