Lyric discussion by El Don 

I agree with most of your interpretations. I would just like to add that "Bullet in the Head" is a statement from Orwell's 1984, in which the protagonist, who is at first independently minded in the end because a faithful follower of his government's propaganda. In the book, Orwell describes this as recieving a bullet in your head.

Here is the exact excerpt from 1984, second-to-last paragraph:

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