Frederick Rzewki’s Which Side Are You On? takes a protest song written in the 1930s by Florence Reese, the wife of a union organizer in the Kentucky coal mines, and explodes it into a gripping, kaleidoscopic set of variations. Ranging from reflection to rage, the piece is a towering sonic representation of these United – and oftentimes Divided – States of America. Pianist and composer Conrad Tao closes the set with a piece of his own, inspired by the writings of Kevin Killian.