The following is not from an inaccurate history book but official documents
Adopted by the JCS at the end of June as JCS 924, “Operations Against Japan Subsequent to Formosa,” it “articulated the JCS consensus on an invasion of Kyushu”4 and warned that taking the Home Islands “might cost us half a million American lives and many times that number wounded.”
SOURCE “Operations Against Japan Subsequent to Formosa,” JCS 924/2, August 30, 1944, 120.
Whether you believe it or not doesn’t really matter because at the time the JCS did.
Oh, I'm not denying that had the US tried to invade the Japanese islands the cost would have been horrific. That's absolutely true. My point was that neither an invasion nor the atomic bombs were necessary, as the Japanese were close to surrender already.
I can't believe I have to put the effort into posting all this again. Maybe I need to save it as a text document and just cut and paste when the subject comes up.
The Soviet Union had an agreement with the Allies that they would enter the Pacific War against Japan once Germany was defeated, and they kept their word, declaring war on Japan effective midnight, August 9, 1945. Is that date coincidental? Not in the slightest. The Allies were made aware of this date in advance.
The rest of this information is important to be taken in context with the fact that even though the Soviet Union was fighting alongside the Allies, neither Truman nor Churchill trusted Stalin, and they suspected the Soviet Union would become a military threat to Europe after the war was over.
Because of this, Truman wanted Stalin to know that the US not only possessed nuclear weapons, but was willing to use them. Hence, the bombing of Hiroshima was set to occur *prior* to the Soviet Union declaring war on Japan, and the bombing of Nagasaki occurred before the Soviet Union could actually accomplish anything. This accomplished many things for Truman:
a: He did not have to order an invasion of the Japanese homeland at the cost of hundreds of thousands of American lives. This practically guaranteed him a reelection.
b: He was able to claim that American military might had ended the war in Japan, completely leaving the Soviet involvement out of it, again, guaranteeing him reelection.
c: He was able to send a warning to Stalin that the US had them and would use them, in hopes of deterring Soviet aggression after the war was over.
d: The US military got to collect real-world data on the effects of nuclear weapons used on real cities with real buildings and real people.
e: The military was also able to compare the different effects of both a gun-type fission weapon and an implosion-type plutonium weapon.
Hiroshima and Nagasaki were more real-world test detonations than they were a strategic attack.
The fact is Japan knew it was in trouble as early as 1942. By 1943, surrender was already being discussed by non-military civilian leaders.
After the Soviet Union declared war on Japan, they immediately invaded Japanese-occupied Manchuria and decimated Japanese forces there. This put Japan in the position of fighting a two-front war against the Allies from the south, where they had established all their defenses, and against the Soviets from the north, where they had no defenses at all.
Based on Japanese historical records, the Soviet invasion had more of an impact on the Japanese surrender than did the destruction of Hiroshima and Nagasaki, primarily because they really didn't understand the significance of what had happened to those cities yet. But the Soviet threat they did understand.
Most historians believe that Japan would have still surrendered due to the Soviet invasion even if the US had not dropped the two atomic bombs. The surrender may have taken a little longer than it did, but it would have still taken place.
In short, stop believing the American-centrist propaganda bullshit you were taught in high school. Did the bombs end the war sooner? Probably. But they were not the primary reason; they were merely one factor in a very complicated situation for Japan, and surrender was already being discussed months before the US even had a working nuclear bomb.
You now have two choices: You can take the blue pill and wake up believing whatever you want to believe. Or you can take the red pill, go verify everything that I have stated here, and see for yourself how deep the WW2 rabbit hole goes.