The article may or may not be making mistakes, it doesn't seem to be available to me on my phone. However this is a topic that has been extensively discussed by historians and the Russian attack is recognized as an important factor in the surrender. Some argue that the atomic bombs were the most important, at the other extreme some argue that the atomic bombs had little or no impact. This is naturally also a topic extensively discussed on AskHistorians.
That is the most recent question we had on it, 15 days ago, which also links the same source.
I've commented on this on r/history before, gonna copy paste the relevant text here plus minor edits for readability.
Most importantly, the news of the atomic bomb did not reach the Japanese leadership until after the Emperor had made it clear his intention to surrender in his inner circle on August 9. This was because the communication lines were completely obliterated, therefore they had to send a team to inspect the situation and so the report was only confirmed on August 10 - after the decision was made. Thus, any claim of a causal link is highly tenuous.
Secondly, as many have stated before, the annihilation of cities was nothing new as the incendiary bomb campaign was already devastating. The deaths of the firebombing campaign numbered 100,000 in the Tokyo campaign on March 9, not to mention the fact that sixty-six other cities were either demolished or partially demolished by the bombing campaign. Additionally, as stated above, the report had to be made by a surveying team hastily, meaning the information gathered was likely insufficient to truly comprehend the magnitude of the bomb.
Alternatively, revisionist historians tend to look at the Soviet invasion as the cause of surrender. The communications between the Soviets and Japanese right before their surrender strongly suggest that the Soviet invasion was what really forced their surrender. While the atomic bomb came after the decision was made, there is a strong chronological chain that dictates the events of the Japanese being betrayed by the once-neutral Soviets until they chose surrender based on their communications.
The reason for this is because the Soviet incursion threatened more than just the lives of the Japanese, it threatened the sovereignty of their land. The Japanese feared that if they did not surrender immediately, they would lose "not only Manchuria, Korea, and Karafuto, but also Hokkaido" - a quote by Prime Minister Suzuki during the debate over surrender.
Traditionalist historians like to argue that the atomic bomb had a major impact but one may find that this was fundamentally political in nature - both for Japanese and Americans.
For the Japanese, it was ultimately the best way for them to surrender while retaining their dignity and land. If they had claimed surrender because of the Soviets, they first admit that they lost the war fairly in military strength. Instead, blaming the atomic bomb allows them to claim it was because of some nearly otherworldly power that was comparable to the celestial might of their Emperor, which is cogent with the narrative of how the bomb was portrayed as a godlike weapon capable of wiping entire cities compared to the firebombing campaign which unarguably achieved far more.
Additionally, the Soviets would have far less negotiating power in the settlements that follow, benefitting both Japanese and Americans. As the Americans were claimed by the Japanese to be the cause of surrender, they would have first pickings in all negotiations with Japan. The Japanese knew that the Americans were far less pernicious than the Soviets in how they treated sovereign land, and so they opted to have them be their overlords rather than the expansionist Soviets.
Lastly, for the Americans, the atomic bomb was a show of force against the Soviets. The atomic bomb was a deterrence tool back then just as much as it is now, even more so as the Soviets had not yet developed their own. The political benefit of showing off their atomic bomb rendered a massive boost to the clout of America in any negotiations; the bomb was a whiff of the strength of a global superpower. Thus, both sides sang the same tune because it was politically beneficial - and historians in the same vein sang along as well, supported by the governments and the documents they were to release.
I've left out a great deal of the subtle details, but do trust me in echoing the views of the revisionists. The subtleties of the events that spanned that critical week or so leading up to surrender are absolutely damning to any and all implication that the atomic bomb was any cause for surrender.
If you're interested in further reading, Tsuyoshi Hasegawa is the man. Speaking English, Russian and Japanese, he's unmatched in his range of covered sources. What I write in this post is essentially me just summarising part of his narrative as far as I can, so you can consider him my main source (the book is Racing the Enemy, on mobile so it's troublesome to copy-paste the full title)
This has been discussed endlessly in other threads on this subreddit (and I need to just make a blog post that I can point people to), but a very short answer:
in the last 15 years or so historians have become increasingly attentive to the fact that the Soviet invasion of Manchuria had a huge effect on the Japanese high command
but disentangling the "effect" of the atomic bombs vs. the Soviet invasion on the Japanese high command is difficult and potentially impossible
there are various people, including those from the WWII period, who have argued that Japan would have surrendered without the atomic bombs (and just the Soviet invasion), there are also those who have argued that it would needed both, there are even those who think they would have folded soon without either and without an invasion (this includes the US Strategic Bombing Survey of 1946)
an even harder question is whether Japan would have surrendered with just the atomic bombs, and not the Soviet invasion — this is rarely asked but sharpens the point much more clearly about causality.
these counterfactuals are interesting even if they are ultimately unanswerable. They call our attention to aspects that get neglected in the "orthodox" and "revisionist" narratives.
For whatever it is worth, my reading of the literature suggests that the Soviet invasion had a big effect on swaying the military forces of the high command towards a surrender, but, again, it is not possible to disentangle the events very easily. It is worth keeping in mind that neither the atomic bombs nor the invasion had an instantaneous effect at getting the Japanese to accept unconditional surrender — the initial Japanese surrender was less than that, and there were several days of negotiation (and even an attempted coup) before the final surrender was achieved.
In any case, the traditional argument — two atomic bombs and they folded up in fear — is oversimplified and missing a lot. There was a lot more going on at the time on the Japanese side of things, to say nothing of the Soviet and American.
If you are interested in getting into the details, Hasegawa's Racing the Enemy does a good job of marshaling the long and drawn-out story of the final days of the war. He falls on the side of the Soviet invasion being a key part of the issue, and thinks the Soviet entry alone might have ended the war (prior to invasion) without the atomic bombs. He also thinks that the bombs without the Soviet entry would not have been compelling. But he also believes that the exact result achieved (the Japanese surrendering in mid-August 1945) was the result of both. It is worth the read if you are curious about these things.
Wow, TIL. In high school (Texas, mid-80s) we were taught:
"We ombed Hiroshima and told the emperor we would drop another one in 3 days if he didn't surrender.
3 days later we bombed Nagasaki and told the emperor we would bomb TOKYO in 3 days if he didn't surrender.
3 days later he surrendered, which was good because we really didn't have another bomb."
I don't remember anything about a Russian invasion.
What do the Japanese say about this? I think they might have the definitive answer.
Follow up, Japanese and US sources said that Japan was negotiating the surrender and verbally agreed 2 days before Hiroshima but the US dropped the bombs anyway. Why were those documents ignored?