I periodically read about studies and military exercises that suggest our missile defense systems are not as impenetrable as we pretend. Similarly, the naval superiority of our aircraft carriers for the same reason.
I am sure we can knock down multiple in flight, but there’s so many out there that all it takes is launching a huge number at once and we’re ash.
What about a scenario where the French had continued their Saar offensive in 1939 rather than withdrawing almost immediately?
Or you could go further back, what if the rest of the world had reacted already at the Italian invasion of Ethiopia or the Japanese on Korea and China?
I think you are confusing two different things. Between the receipt of the Potsdam text and the actual surrender on August 15, the debate within Japan concerned preserving the Kokutai. The issue of the American investigation into the Emperor’s role in the conduct of the war came after MacArthur’s landing. Both are pretty extensively documented.
To return to your previous point, even Japanese research into heavy water for potential weaponization has also been documented and its also clear that they did not have any clear idea of American progress on this matter. Furthermore the Imperial army simply did not care if the Americans had one atomic bomb or one hundred, they were fully prepared for what was called the Decisive Battle on Japanese soil based on knowledge of American troop movements towards Japan.