S'far as I know, the driving force behind the trio getting any politics into their sets was Joe Frazier. Gem of a man, intelligent and forthright. He was/is aware of politics and has a deep passion for social justice.

The one I loved a great deal was a Silverstein song entitled "Business Goes On As Usual." The trio did it wonderfully, imo.
(I think it was called that. If not, that's the first line of the song.