Guest, whichever Guest you are, you're a pillock of the first order.

Truman repeatedly delayed acceptance of the Japanese government's conditional surrender attempts until after both types of A-bomb had been used.

The significant words in this are "conditional surrender". Parenthesis. Since May, I now work for Pearson Group, whose imprints include Pearson Education, Penguin, Puffin, & Longmans, amongst others. We have a library at work, so when I can find time to take a break, guess where I spend it, amongst history books a-plenty. Heaven! :)

What I am basing my following points on is a book I have lately been reading called "More What If..." (link here) which includes essays on how nearly Truman didn't become President, & what might have happened if The Bomb hadn't been dropped. I can't quote the essayists sources off the top of my head, & I have no idea what his biases might be, but this, in a nutshell, is what the historian who speculated on The Bomb scenario had to say.

Fact: Japan was ruled by a small military clique. I forget the exact number, but it's something like 6 or 7 people deciding the fate of the entire nation, with unquestioning obedience at their beck & call from the population at large.

Fact: Conditional surrender, which is all that was on offer from the Japanese, meant a surrender in which all the existing power structures remained in place. Does anyone, even Stilly River Sage, think this was an acceptable proposition?

Fact: The ruling clique was perfectly prepared to spend thousands & millions of Japanese lives (never mind Allied casualties) in an effort to force the Allies to accept a conditional surrender on the above terms. They knew they were beaten, but they (very humanly, if very inhumanely) sought surrender on the most advantageous terms. I ask again, does anyone, even Stilly River Sage, think this was an acceptable proposition?

Fact: With the exception of Douglas MacArthur (who was rather Patton-esque in many respects, especially as regards his estimation of his own abilities - sorry, that's somewhat my opinion, rather than quoted fact!), the majority of the the senior US commanders, particularly Navy bods, were unenthusiastic (to say the least) about the prospects of invading Japan.

Fact: Geographical limitations determined & limited the possible beach-heads for any American invasion of Japan. Hindsight has established that the Japanese high command (limited in certain respects, but not stupid) had correctly identified every single possibility & defended appropriately. Any invasion would have resulted in absolute carnage. Okinawa would have been a picnic by comparison & the American command knew it. Conservative casualty estimates run way beyond the million mark (try 2-3 million for size), making Hiroshima & Nagasaki small beer by comparison.

Probability: It is likely that Hirohito had far more power, authority & knowledge than the Allies quite deliberately let everyone believe. There are strong indications that quite late in 1945, Hirohito was still in favour of continuing the war.

Truman's decision was never going to be a good one to have to make. It was a choice between diabolical & far worse. SRS & anonymous guests can bleat all they want about "dogma" & "war criminals". Given the choice he had to make, Truman would have had to have been mad or stupid to have done otherwise. It was a horrible choice, even if he knew (which I doubt he did or could have) the full consequences. Nevertheless, I believe he not only saved thousands of American lives, by condemning H & N, I believe he also saved hundreds of thousands of Japanese (& maybe Russian too) lives. Plus, on the whole, he ultimately created a better society for all of those survivors.