The Pacific Ocean War of World War Two was an all-out declared war. No holds barred.
At no point did Japan stand down or offer any kind of terms.
Japan did not waver in the severity of their military conquests.
They were fighting to the end.
Without nuclear weapons, the Allies would have conducted an opposed amphibious landing on the Japanese homeland islands.
We already knew from reading their communications that the Japanese army had figured out where we would land.
So it would have been a protracted mess with hundreds of thousands or millions of casualties.
Nuclear weapons were no worse than the firebomb raids we were already conducting.
There was and is no special evil associated with the word “nuclear”.
We just threw everything we had into the Pacific Ocean war portion of World War Two.
We were making about two nuclear bombs per month.
Japan might have test fired one nuclear bomb. [In fact, the current North Korean nuclear weapons program might well be based on Japan’s Navy’s World War Two nuclear weapons program based near Wonson.] [Some of us disagree on the details. But a lot of the details remain “shrouded” as the Japanese participants were fearful of being punished for participating in the Japanese nuclear weapons program.]
There are differences of opinion as to whether Japan and Germany had an atomic bomb or if they were working on one.
You could call it a “uranium bomb” instead of a nuclear weapon. In fact, Germany did ship a submarine full of uranium [
German submarine U-234 - Wikipedia] to Japan with the intention that Japan should use that shipment to build a nuclear weapon to use on the Americans. That particular German shipment of uranium to Japan got diverted to the United States when the German government surrendered.
Unknown to the Americans, Japan had constructed the I-400 Class of gigantic submarines. They built three of them and depending on the size of their nuclear weapon, they could have used their I-400’s to deliver a nuke to the United States or perhaps to destroy the U.S. invasion fleet.
In addition to the B-29 bomber, the U.S. also built the B-32, which was the same size, but built in smaller numbers. In addition, the U.S. also designed the B-36 bomber which was much larger and had ten engines and eventually built around 400 of them; it could stay up for almost 48 hours without refueling.
In addition, Germany had developed a long range “bomber”
Junkers Ju 390 - Wikipedia
In his book, The Bunker, author James P. O’Donnell mentions a flight to Japan. O’Donnell claimed that Albert Speer, in an early 1970s telephone interview, stated that there had been a secret Ju 390 flight to Japan “late in the war”. The flight, by a Luftwaffe test pilot, had supposedly been nonstop via the polar route.[16] O’Donnell is the sole source for the story. Speer never mentioned the story in any of his writings or other interviews. Kössler and Ott make no mention of the claim.