There is absolutely no doubt in my mind that 1) had the atomic bombs somehow malfunctioned, or 2) Truman somehow had the misguided balls to stop a two billion dollar project dead in its tracks without using the weapons --- we would had to have invaded Japan at the cost of hundreds of thousands of US lives, and most likely -- through more B-29 incendiary and carpet bombing, starvation because of the naval blockade, and suicidal resistance to our amphibious landings --- millions of Japanese.
In addition, Marshall was planning on using atomic bombs as tactical weapons on beachheads and troop concentrations, in the event of invasion.
Talk about unimaginable....that is exactly why Hirohito and the "peace" faction in the Japanese were finally able to overcome the fanatical resistance of the military...the military had nothing to offer the Japanese people but genocidal and cultural extinction.
The women and children had little to do with making the decisions. In that society, such folk simply lived there. Those few who survived the attack and live on today certainly should not be blamed for it, which, unfortunately, is what thugs and louts prefer to do every single time.