It's an unoriginal and somewhat out-of-place Planet of the Apes reference, is all:
http://en.wikipedia.org/wiki/Beneath_the_Planet_of_the_Apes#Plot
I guess they thought that they were being clever:
Honestly though, I think the guys at Bethesda probably got it from watching the Futurama episode which made the exact same reference first.
http://en.wikipedia.org/wiki/Beneath_the_Planet_of_the_Apes#Plot
I guess they thought that they were being clever:
"...and finds a person inside, kneeling before the high altar. However, the object of worship fills him with horror - an intact nuclear intercontinental ballistic missile"
Honestly though, I think the guys at Bethesda probably got it from watching the Futurama episode which made the exact same reference first.