I've never quite got my head around why it had to happen. Was Truman convinced the Japanese would carry on fighting for ever, despite the Germans already being screwed back in May? Was it more a case of long-term strategy, limiting the Soviets' postwar influence (they were about to join the offensive against Japan) and a show of strength to them?
It was used as an alternative to invading Japan, codenamed Operation Downfall, which the US didn't really want to do as it would likely result in the deaths of millions, including millions of civilians. On top of that, because of it's geographical location, the Japanese knew exactly where the US would attack. The invasion of Japan would very likely have been the bloodiest and most costly battle of the war. There may well of been some Cold War undertones in it too like you mentioned.
The Japanese were set to surrender anyway, and the Americans knew that. The fear was Russia moving in at the other end, and it was more to deter that, rather than prompt the Japanese.
They really weren't. Japan were preparing for the US to invade them. You might want to have a read of this. https://en.wikipedia.org/wiki/Operation_Downfall#Operation_Ketsug.C5.8D
I've just been reading a book that went into a fair bit of detail and contained quotes from those involved from all sides. I followed it up with a quick scan on google, and by coincidence, there were a few programmes with bits about it. I'm happy to have a read of your link later, and compare it to the quotes and recollections I've been reading/viewing.
I'm sure I read somewhere that, because the bomb dropped on Nagasaki five days later was a different type ('Fat Man') from that used at Hiroshima ('Little Boy'), there was a fear for the U.S. that Japan would surrender before 'Fat Man' could be tested. The bombing date was hastily moved forward...
I've had a quick skim of the posted link, so it's possible I've missed the key it you're referring to, but much of that seems to stop short of the US Russia politics and seems to Co firm the Japanese knew their time was close, if not already up. Do you have a link about what you see as the Russian element? I had a quick Google of did the bomb cause the Japanese surender and most seem to relate to the Russian threat as being a key time line for the US to drop it. If I get chance, there's some I teresting stuff showing discussions pre bomb, where surrender terms were eing debated by both sides. The surrender seemed decided, only the terms were being debated.
The USSR were being slow in committing to invade Japan. The Yanks were encouraging them to, not discouraging them. The Yanks decided to use this weapon rather than try landings, which given the Japanese attitude at the time regarding surrender would have been a protracted bloodbath and probably have resulted in more civilian deaths than the atomic bombs caused (see how many were killed in conventional raids on Tokyo, Yokohama etc). Another factor was the bomb acted as a warning to Stalin not to occupy even more of Europe, which he probably would have done as a few million more deaths were of little concern to him. His lies regarding free elections in countries "liberated" by the USSR and their imposition of communist regimes demonstrates his goals. Of course the most pertinent question is does anyone seriously think that if they had been first to make the bomb Germany wouldn't have obliterated London or Moscow, or the Soviets wouldn't have wiped out Berlin, or the Japanese been quite happy to use it.
The bomb on Nagasaki was dropped on Aug 9th only 3 days after Hiroshima. A guy living in Hiroshima survived the bombing and then went to Nagasaki to be with relations and experienced that bomb. He survived and only died a few years ago. My wife was born exactly 3 years before the Hiroshima bomb incident.
A collection of drawings by Hiroshima survivors... please log in to view this image http://edition.cnn.com/2015/08/04/world/gallery/hiroshima-70th-anniversary-drawings/index.html
Quill's right. The American Marines had Island hopped all around the Pacific and the closer and closer to the Japanese mainland they got, the more desperate the Japs were becoming. Kamikazes, mass suicide's rather than surrendering etc. My grandad fought them in Burma & said they were fanatical. The fighting was slow and the USA was losing a lot of men. It also was supposed to be a show of strength. One that the Russians responded to.
I think, thinking back on all that I have watched and read, my thoughts are that this desire to halt allied deaths was the imperative. Japan is made up of thousands of islands and their people had more than adequately shown their determination to defend vanquished soil, their determination to defend their own soil was something the allied forces really did not want to test - would you? I think the Russian deterrent would have been very real - Churchill never wanted us to stop prosecuting action against the Russians - just as I would think the political boffins would have relished an opportunity for a full field test of their genius (sic). It's a great discussion point, but, most of all, I hope with all of my heart, that it will forever be the only such discussion point.