"Letterbomb" is the 10th track on Green Day's American Idiot album. It is 4 minutes and 6 seconds in duration. It is in the key of E, a common key signature for punk rock songs, but more relevantly it is one of only two songs (the other is "Whatsername") on the entire album not with a key signature of G, A-flat, A (which are each only a semitone apart), or F minor in any part of the song. This radically different key signature subconsciously makes the listener aware that this song marks a transition, both in the album's tone and the continually unfolding story of Jesus of Suburbia.