I'm pretty sure if you write for a Communist newspaper and talk a lot about being a Communist you're a Communist regardless of whether or not you ever actually joined the party.
fifty bajillion stars for this being on PoE at all, one of my favorite clips ever, bar none.
unfortunately the entire thing is a soundstage...i did a research essay on Sonny Terry and Brownie McGhee not too long ago and was a little disappointed to discover this whole thing was a set shot. i still play this song, though!