[Conventional bombing did not break the spirit of the Japanese fanatics in WW II. So I doubt if it will break the spirit of the Islamic fanatics in Afghanistan now.]
https://en.wikipedia.org/wiki/World_War_II_casualties#Total_deaths_by_country
https://en.wikipedia.org/wiki/War_in_Afghanistan_(2001%E2%80%93present)
The principal reason this war is dragging on is because we haven’t taken the gloves off. Genghis Khan is said to have wipe out entire cities. I’m a little skeptical, because they lived off the land (i.e. local civilians). No local civilians, no food. If you kill them all, what do you do for food on the way back from an expedition? You can’t carry it all with you. Draft animals need to be fed and watered, etc etc. But even Alexander, over a thousand years prior to the Mongols, killed vast numbers of people in cities that resisted him:
https://en.wikipedia.org/wiki/Battle_of_Thebes#Destruction_of_Thebes
https://en.wikipedia.org/wiki/Siege_of_Tyre_(332_BC)#Conclusion_of_the_siege
https://en.wikipedia.org/wiki/Siege_of_Gaza#Consequences_of_the_siege
https://www.livius.org/sources/content/diodorus/alexander-sacks-persepolis/
> Actually, they [the Japanese in 1945] were near the breaking point. <
True enough. But without both A-bombs they still would not have surrendered.
> The principal reason this war is dragging on is because we havent taken the gloves off. <
I certainly agree with that. And thats 100% on Bush II. Right after 9/11 the entire West was with us. America was united. NATO was ready to be activated. But instead of total war, Bush decided to go with a mushy blend of police-action and nation-building while the Taliban was still unbroken.
But wait. It gets worse. Bush then decided to invade Iraq. That would be as if FDR decided to invade Russia soon after Pearl Harbor. Bush II did perhaps irreparable harm to this country. He can go straight to... (I better stop here).