Yeah it's like wakin' up from a bad dream
Just to figure out you wasn't dreamin' in the first place
This introduction seems to be a play on the idea of the “American dream”. While most view the American dream as freedom and the promise of the possibility for prosperity (props to Wiki), or the visual of having a white picket fence with the perfect family and life, Nas is waking up to something completely different (a bad dream), which he further explains in the song.
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