Big Rock Candy Moutain is an old Pre WWII socialist song about a socialist Utopia. And the Donks are still pushing the same ideology. Nothing new, just dressed up differently.
Every time I here Booker, Harris or AOC talking about reparations, free medicare for all, and free college, I hear that tune playing in my head, LOL.
I only know it from the soundtrack of O Brother Where Art Thou.