I did pick up on it cause the Tactics team loves reusing real history for their storylines. Of course the subject of the atomic bomb in WWII is a very popular topic in Japanese culture. In many stories, characters deal with forces or weapons that mimic the atomic weapon. MGS, Front Mission 3, and several anime's concern themselves with atomic weapons or artifacts that share heavy parallels with the atomic bomb. Its interesting to note that when thinking of Nethicite in this context, that FFXII can be seen also as having a strong anti-nuclear weapon message behind it.

Course, XII to me at least, has many strong messages that parallel to our modern times. Its less a fantastical story as much as a parable of the modern state of affairs in the world itself. Thus the game's plot serves as a message to teach people while entertaining them.