(a city with military production, sure sure, but they were choosen not because of military value, but because they were relatively undamaged, so the effect of the bombs could be studied. Concern for loss of japan civilian live was never an issue)
There only existed two bombs at the time. Had the bombs been dropped as a show of force, it is very likely the US and Japan would have to suffer through a costly invasion anyway.
[1] https://en.wikipedia.org/wiki/Demon_core
[2] https://www.atomicheritage.org/history/timeline search for 1945 July 23 entry.
The US built a massive manufacturing pipeline to make nuclear weapons. Little boy was a once off. Fat man was basically a functional prototype. And the manufacturing pipeline was running and kept running after the war. How much weapons grade plutonium they had left over after they bombed Nagasaki is kind of a quibble.
Why would a demonstration need to be told the japanese in advance?
And a dud could have also happened to the one used on hiroshima.
A shock effect could have been achieved by a bomb detonated close to Tokyo. And with papers dropped, saying, this will happen to all your cities, soon.
To this end, Stalin and Molotov strung out the negotiations with the Japanese, giving them false hope of a Soviet-mediated peace. [..] The Japanese would have to surrender unconditionally to all the Allies. To prolong the war, the Soviets opposed any attempt to weaken this requirement.[56] This would give the Soviets time to complete the transfer of their troops from the Western Front to the Far East, and conquer Manchuria, Inner Mongolia, northern Korea, South Sakhalin, the Kuriles, and possibly Hokkaidō - https://en.wikipedia.org/wiki/Surrender_of_Japan#Soviet_inte...
However, the Japanese presented no formal terms, because details were to be worked out by negotiation. - https://www.quora.com/When-Japan-offered-conditional-surrend...
Edit as reply due to rate limit:
The article you linked doesn't support the claims you made about Japan's conditional surrender. The closest it comes is "Anami wanted retention of the emperor, self-disarmament, no foreign occupation, and trial of any Japanese war criminals by Japan itself". But that is what Anami wanted, not what was written down in some final, take-it-or-leave-it offer. And that's from before the Soviet declaration of war.
In fact the article basically contradicts your claim about the necessity of the bombs:
> The bomb played a part in Japan’s surrender, but it may not have been necessary, he said. Had the U.S. drawn Stalin into publicly supporting the Potsdam Declaration’s unconditional surrender demand, Japan might not have held out hope for a Soviet-brokered deal. Had it guaranteed the emperor’s position, Japan might have surrendered earlier, Hasegawa said, though this is yet another point that draws endless historical debate.
> “Other alternatives were available, but they were not explored,” Hasegawa said.
Choosing the bombs over merely exploring other options is rather damning, don't you think?
""Hoshina Memorandum" on the Emperor's "Sacred Decision [go-seidan]," 9-10 August, 1945 Source: Zenshiro Hoshina, Daitoa Senso Hishi: Hoshina Zenshiro Kaiso-roku [Secret History of the Greater East Asia War: Memoir of Zenshiro Hoshina] (Tokyo, Japan: Hara-Shobo, 1975), excerpts from Section 5, "The Emperor made go-seidan [= the sacred decision] – the decision to terminate the war," 139-149 [translation by Hikaru Tajima]
"An overview of the destruction of Hiroshima [undated, circa August-September 1945] (Photo from U.S. National Archives, RG 306-NT) Despite the bombing of Hiroshima, the Soviet declaration of war, and growing worry about domestic instability, the Japanese cabinet (whose decisions required unanimity) could not form a consensus to accept the Potsdam Declaration. Members of the Supreme War Council—“the Big Six”[46]—wanted the reply to Potsdam to include at least four conditions (e.g., no occupation, voluntary disarmament); they were willing to fight to the finish. The peace party, however, deftly maneuvered to break the stalemate by persuading a reluctant emperor to intervene. According to Hasegawa, Hirohito had become convinced that the preservation of the monarchy was at stake. Late in the evening of 9 August, the emperor and his advisers met in the bomb shelter of the Imperial Palace.
"Zenshiro Hoshina, a senior naval official, attended the conference and prepared a detailed account. With Prime Minister Suzuki presiding, each of the ministers had a chance to state his view directly to Hirohito. While Army Minister Anami tacitly threatened a coup (“civil war”), the emperor accepted the majority view that the reply to the Potsdam declaration should include only one condition not the four urged by “Big Six.” Nevertheless, the condition that Hirohito accepted was not the one that foreign minister Togo had brought to the conference. What was at stake was the definition of the kokutai (national policy). Togo’s proposal would have been generally consistent with a constitutional monarchy because it defined the kokutai narrowly as the emperor and the imperial household. What Hirohito accepted, however, was a proposal by the extreme nationalist Kiichiro Hiranuma which drew upon prevailing understandings of the kokutai: the “mythical notion” that the emperor was a living god. “This was the affirmation of the emperor’s theocratic powers, unencumbered by any law, based on Shinto gods in antiquity, and totally incompatible with a constitutional monarchy.” Thus, the Japanese response to the Potsdam declaration opposed “any demand which prejudices the prerogatives of his Majesty as a sovereign ruler.” This proved to be unacceptable to the Truman administration."
The military fervently wanted a US invasion, believing it could inflict millions of casualties and then negotiate better terms. And many Japanese didn’t feel like they had even lost yet, they were willing to endure bombings feeling their fortress island was unassailable.
https://www.stripes.com/news/special-reports/world-war-ii-th...
Many of who resumed as they did during the War in the re-construction phase, I highly recommend the book: A Nazi in Exile. Its about Martin Bormann, a high ranking SS lieutenant close to Hitler who was already making deals in what seemed like the inevitable defeat of Germany, Italy and Japan by 1943-44 or so and starting to ensure it funneled its funds out of Germany into Switzerland and helped the biggest corporations (on both sides) continue to thrive in the post-war economy.
Many of whom still remain as monoliths to this day.
I think all this does is re-enforce General Butler's claim that: War is a racket. Everything else is just footnotes that often contradict and conflict with one another to obscure the obvious fact that no one 'wins' in War except a very small collective few in Banks, Industry that shape war policy for other Poor people to fight.
And the US ultimately did accept a surrender on the condition that the imperial family not be tried for war crimes (a particularly contentious point for China, since a royal family member was the commanding officer in charge of the forces that perpetrated the crimes at Nanking).
That is brought an end to the war with fewer casualties, both American and Japanese even moreso, is not a difficult claim to support. Japan planned to fight a defensive war against an amphibious invasion in order to negotiate more favorable surrender terms. The Japanese estimated that this would incur 20 million Japanese casualties, and this plan was approved. Even if we assume that Japan's war machine would collapse before this figure of lives lost was reached, it is almost certain that the death toll would be in the millions. Germany, without the advantage of being a mountainous island nation and having a lower population than Japan, fought on its own soil in 1945 to the effect of several million dead. Thus, it's almost certain that the atomic bombings resulted in an order of magnitude fewer Japanese lives lost than an conventional invasion.