Hiroshima was the headquarters of the Fifth Division and Field Marshal Shunroku Hata's 2nd General Army Headquarters, which commanded the defense of all of southern Japan. It was also a communications center, a storage point, an assembly area for troops, and was a military-industrial center powered by the mass-scale forced labour of Koreans known as hibakusha. The Hiroshima island of Edajima hosted the Navy Elite Academy. Kure, around 20 km from Hiroshima, was also known for a military port and navy factories. The famous giant warship, Yamato, was constructed in Kure. The material and labour for Kure came from Hiroshima.McCulloch wrote: Would as many lives been saved if the target was more of a military one away from a civilian population center?
Nagasaki was one of the largest sea ports in southern Japan and had wide-ranging industrial importance. Ordnance, ships, military equipment, and other war materials were manufactured there. The Mitsubishi Steel and Arms Works was located there. Mitsubishi produced over 10,000 Zero fighters and the battleship Musashi.
Because the first one didn't cause Japan to surrender. If the second one hadn't caused them to surrender I assume we would have detonated a third. We can second-guess all we want, but the fact is our actions achieved the goal of the surrender of Japan.Would that not have shown as effectively to the Japanese leaders the awesome new capability of the American military? And having dropped one, why was the second civilian target necessary?