(1) Hitertho, I have cited three authors, Kagan, Bernstein and Sadao. All of them are scholars. All of them disagree with your views (despite your insinuation that no credible academic would do so). Kagan's extensive credentials are available on Yale's website, here.
(2) I concede that I mistakenly characterized Kagan's article as peer-reviewed off-site; that mistake bears no relevance to the veracity of Kagain's analysis (which you have yet to challenge beyond gainsaying and appealing to his alleged partisanship). The reason I did not provide a link is because I had downloaded the article as a PDF.
(3) All views on whether the use of atomic weaponry was appropriate, including Alperovitz's (whose views are challenged by modern revisionists), are inherently value judgements.
(4) Secondary sources are predicated on, and include references to, primary material. That is evidenced by the sources I have presented here.
On the basis that speculation and moral judgements cannot be disproven, Nimitz, Eisenhower and Leahy weren't "wrong". Notwithstanding, the following points need to be taken into consideration:
(1) No one has speculated that Japan wouldn't have been defeated sans atomic weaponry. It has instead been argued that there is significant evidence indicating that use of the a-bomb shortened the war and overcame the need for the US to invade Japan.
(2) It is is not surprising that conventional military leaders like Eisenhower, Leahy and Nimitz were deeply sceptical of the a-bomb, given the extent to which it revolutionized human conflict (and therefore challenged the military orthodoxy). Even so, and to the best of my knowledge, all three men were advocates of the bombing campaigns and constrictive blockades which, by your own admission, caused more civilian suffering than the atomic attacks.
(3) The comments of these men do not indicate that Japan agreed to the Potsdam terms solely because of the Soviet intervention (which is your main thesis). Nor do they prove that alignment with orthodox position is anti-intellectual or ahistorical. They serve only to represent the view that the use of atomic weaponry was not necessary to end the war (a point which, as mentioned above, is largely undisputed).
My interlocutor appeared to claim that the Imperial Rescript on Surrender specifically mentioned the Soviet entry into the war as the reason for the surrender. I posted the transcript of the speech to show that this was false.
The reasons for the delay were as follows:
(1) Leading gov't figures were not immediately sure, either of the extent of the damage or whether atomic weapons had actually been used (Togo confirmed that atomic weaponry had been used through American broadcasts on the 7th and called a meeting of senior cabinet minsters the same day).
(2) The militarists, in typically defiant fashion, sought to minimize the impact of the bomb and obstructed the meeting of the Principals out of a zealous and delusional opposition to surrender (which they knew was the purpose of summoning the council).
Notwithstanding, even if the leadership did not meet until the 9th, the decision to convene the Supreme Council came on the 8th, a day before the Soviet declaration of war. This disproves the theory that the Principals were unmoved by the bombings and only hurriedly met after the Russian intervention.
No one has argued that the damage caused by the atomic bombings was more extensive than the entirety of the conventional allied bombing campaign. The obvious distinction between atomic weaponry and conventional weaponry (which the Japanese leadership recognized) was the magnitude of the destruction which the former could cause in a single strike. It rendered the hold-out strategy insisted upon by the military obsolete, and, as the sources show, clearly influenced the emperor in his decision to break the deadlock between the factions.
Setting that aside, the point you make here is self-contradictory: on the one hand you want us to believe that the atomic bombings were so uniquely evil in their destructivity that they violated a criminal threshold; on the other you try to pass them off as being routine, as being so indistinct in their effect from conventional carpet bombing that the Japanese leadership was neither shocked nor moved by them.