If anyone needs to understand or if the already-knowledgeable could use a reminder why the war needed to be ended as soon as possible and by whatever means necessary, pick up any of countless books about how the Japanese army treated everyone under their control, both POWs and occupied peoples.

I have read many such accounts myself dating back 60+ years to my teens, and I’ve just started another, The Devil’s Doctors: Japanese Human Experiments on Allied Prisoners of War by Mark Felton (yes, the YouTube guy). As I’ve gotten older, my tolerance for reading such accounts has diminished, but this one evidently covers specifics that I was less familiar with, and I’m curious about.

It’s impossible to think of strong enough adjectives to describe how depraved and horrible the Japanese army’s conduct was from its invasion of China in 1931 to when the US finally ended the war. And although apologists will point to the fact that surrender was considered to be dishonorable for military personnel and that their own low-ranking soldiers were treated brutally, what is usually ignored is that they treated other Asians as badly as the POWs, and in many cases worse. Descriptions of what Unit 731 and similar operations under its control did to Chinese civilians and others are beyond imagining. As is true in any war, many innocent Japanese suffered for the sins of their fathers, but the use of the atomic bombs helped to end that suffering sooner than later.

My great uncle was a WW1 veteran and a civilian contractor working at the first test site; he witnessed this test. He retired and lived his life in Albuquerque and became a passionate artist, painting landscapes of the southwest. He painted the first atomic bomb detonation from his memory. I think one of my siblings has it. I'd like to post a photo here when I locate it.

As sigfreund noted above, the use of the atomic bomb probably reduced Japanese casualties too. It induced Hirohito to surrender.

I asked GROK what the plus/minus on Japanese lives was by ending the war with the bomb vs the conventional invasion plan.
The number was uncertain but clearly saved millions of Japanese lives, not to mention ours.