I think that the song is generally about being in love with a girl but not being sure if he really deserves her. "how would I explain your body to the rest of my day" is probably a sexual reference and the almost nonsensical comparison to the interstates might be a metaphor for how he can't give her the things she wants in life.
I think that the song is generally about being in love with a girl but not being sure if he really deserves her. "how would I explain your body to the rest of my day" is probably a sexual reference and the almost nonsensical comparison to the interstates might be a metaphor for how he can't give her the things she wants in life.