Conrad Keely told The Skinny that this tune with a group-sung chorus is the only song that he's ever written on tour. He explained: "Sonic Youth were playing at Pukkelpop Festival, we were just about to go on stage and I wrote this pretty spontaneously in the back of the bus. It's about the feelings I have sometimes about not wanting to get on stage, not always wanting to be in the limelight and scrutinised. It's really hard to compose on tour, to find the space and the clarity of mind. I just forced myself to do it and this was the result. I'd like to do more of that, I always hear about other composers who can. I mean, The Beatles wrote some of their best work on the road. Maybe it's my own lack of trying, but with the momentum that I feel from this recent record, I feel as though I'm undergoing this creative surge and I want to continue to mine that."
The Prince-penned "Manic Monday" was the first song The Bangles heard coming from a car radio, but "Eternal Flame" is closest to Susanna's heart, perhaps because she sang it in "various states of undress."