On Okinawa alone, the body count of Japanese came to 107,000 men and 11,000 prisoners of war. Another 25,000 men were apprently killed and sealed in caves. The Japanese had lost 7,800 aircraft in the concentrated attacks on the island and its environs or ten times as many as the Americans, but the American casualties in the taking of Okinawa alone had been heavy: about 75,000 officers and men.
So with this experience in the battle zone, it became all the more alluring to use the most expensive and most effective secret weapon of WW2...the Atom bomb.