I'm amazed at how readily accepting some are of using nuclear weapons.
It will always bring about a quicker end to a conflict. If that's your only justification, you would support it every time.
Is that really what you think America should be? Remember - a nuke is a WMD. I thought only rogue nations used those? That they were immoral and villainous?
Targeting civilian populations is utterly immoral.
But unfortunately, targeting civilian populations had been going on since 1939, by both sides.
The question is not whether Japan would surrender. Surrender can take many forms.
The allies strategic goal was to coerce Japan to submit to the Pottsdam Accord. The goal was not just to get Japan to stop fighting.
The Pottsdam Accord required Japan to:
Surrender unconditionally
Have their sovereignty limited to the four home islands
Have their government be forced to respect human rights
Have leadership in their government held accountable for the war.
If Japan did to submit to these demands, the Accord explicitly said Japan faced utter destruction.
Which was obviously code word for the atomic bomb.
Yes, Japan made appeals to the USSR to mediate a peace more favorable to Japan. This was one time the Soviet Union stood shoulder to shoulder with USA. They had signed into the Pottsdam Accord, and they were not going to entertain Japan's attempts for better surrender conditions. Their answer to Japan's entreaties was to attack Japanese forces in Manchuria.
So realistically we have to ask what it would have taken to coerce Japan to submit to the Pottsdam Accord. Could a simple naval blockade have coerced them to submit? That is open to debate, but many people find it highly doubtful.
Any hypotheticals about how the war could have been ended has to result in coercing Japan into submitting to the Pottsdam Accord, to submit to a military occupation, to submit to having their government dismantled, to submit to having their warrior ethos dismantled, to submit to a war crimes tribunal, to submit to having a pacifist constitution forced on them.
That is a tall order to have any sovereign nation to submit to, especially one with a warrior ethos like Japan. Even after Russia's utter defeat to Germany in 1917, Russia still came to terms to keep its government and sovereignty over most of traditional Russian territory.
Is it possible we could have coerced Japan to submitting to all the Pottsdam demands simply by a naval blockade or some other less destructive strategy? I do not know, but many think it unlikely.