Not that would stand up against the million plus combatants propossed invasion force - it was planned to be bigger than Normandy after the difficulties encountered during the island hoping battles - but the A-bombs became 'online' and so, lives were inevitably saved on all sides. (methinks that the 3rd bomb was still being made/processed, and when ready, was used in the 'Baker' test in '45/'46 - hence why the quick use of the 2nd upon Nagasaki, to create the appearance of more waiting, and weaken the nearest regional command centre to the propossed invasion axis via Kyushu after the next invasion step onto Honshu, which was the 1st bomb target of Hiroshima... sorry I am getting off-topic.)
After Phillipines Sea and Leyte, very few in Japan believed they could achieve victory. The battles in 1945 were about making the achievement of final victory by the allies so expensive that better terms than those offered at potsdam could be obtained. The Japanese in 1945 had two basic war aims....that any peace treaty respect the authority and person of the emperor, and secondly that the Home Islands not be the subject of foreign occupation. They achieved one of those aims.....the empereor was respected, his position in the government retained of sorts. He had to make declarations after the war that he was not a deity, but the Americans did honour their undertakings (only ever given verbally) that neither he or any member of his immediate family would be subject to war crimes trials or similar. Thats a bit of an embarrassment, since at least one senior memeber of the royal family was responsible for the massacres at Nanking.
The A-Bombs had an undoubted effect on japanese thinking, but a more important element in their final agreement to surrender was the Soviet invasion of Manchuria
One discussion of this alternative viewpoint can be found here...
Why did Japan surrender? - The Boston Globe
The article doesnt bring it out so well, but if you get the relevant transcripts from the japanese war cabinet, it imedialtely becomes apparent that the bombs were not their prime motivation for surrender. The cabinet was essentially deadlocked, they asked the emperor for guidance and he indicated that surrender was the best option.....the cabinet then discussed why that might be so, and it was the Russian invasion that influenced them far more than the bombs.
"In recent years, however, a new interpretation of events has emerged. Tsuyoshi Hasegawa - a highly respected historian at the University of California, Santa Barbara - has marshaled compelling evidence that it was the Soviet entry into the Pacific conflict, not Hiroshima and Nagasaki, that forced Japan's surrender. His interpretation could force a new accounting of the moral meaning of the atomic attack. It also raises provocative questions about nuclear deterrence, a foundation stone of military strategy in the postwar period. And it suggests that we could be headed towards an utterly different understanding of how, and why, the Second World War came to its conclusion.
"
Hasegawa has changed my mind," says Richard Rhodes, the Pulitzer Prize-winning author of "
The Making of the Atomic Bomb." "The Japanese decision to surrender was not driven by the two bombings."
President Truman's decision to go nuclear has long been a source of controversy. Many, of course, have argued that attacking civilians can never be justified. Then, in the 1960s, a "revisionist school" of historians suggested that Japan was in fact close to surrendering before Hiroshima - that the bombing was not necessary, and that Truman gave the go-ahead primarily to intimidate the Soviet Union with our new power.
Hasegawa - who was born in Japan and has taught in the United States since 1990, and who reads English, Japanese, and Russian - rejects both the traditional and revisionist positions. According to his close examination of the evidence, Japan was not poised to surrender before Hiroshima, as the revisionists argued, nor was it ready to give in immediately after the atomic bomb, as traditionalists have always seen it. Instead, it took the Soviet declaration of war on Japan, several days after Hiroshima, to bring the capitulation".