What does the song Castle of Glass by Linkin Park mean?

Answer 1

This song is mostly based upon a Warrior's hard life. However, it has other meanings too-

1) The warrior's life- How a warrior is forced to live a life for others and protecting them, and how he wishes to be let free and return to his family. The Castle of Glass chorus refers to his presence being invisible in a large army (only a crack that is hard to see) but is very significant in something very weak (a crack specially in a stronghold of glass breaks everything apart).

2) A sinner's life- How he asks for redemption and a chance to improve. Again he is something small in a system completely wrong (suppose violence or drugs).

3) A lonely person's life- Suppose a person was recently separated from a loved one of his, he wants to be whole again and given a chance to relive those moments as the warming lyrics say. His current situation is a crack in his fragile and broken life (his castle of glass).

Note:Cause I'm only a crack- referring to someone's situation as a very beginning of something big

In this Castle of Glass- the Big thing is something that is very weak and unstable, like a stronghold of glass.

Hardly anything there, for you to see- Yet it is all unobservable, though it seems that the person may be significant to his loved ones but not to the army he belongs to (crack).

It means that "I" is someone small and unobservable to the extent of negligence, almost invisible (like a crack in glass), yet plays a big role in the breaking down of something that his faulty.