It is partly about emigration to America. The two protagonists dream is escaping their squalid lives for a new life in the US.
"I can see a better time
When all our dreams come true
They've got cars big as bars
They've got rivers of gold"
However, the 'story' is about someone dying (in the drunk tank) and the other person s anger them dying and at their unfulfilled dreams.
"You're an old **** on junk
Lying there almost dead on a drip in that bed"
Can't make it all alone
I've built my dreams around you"