What's an anthem? It's a stirring call to arms or an expression of collective emotion. Sometimes it's a recognition of injustice, a representation of an oppressed group, or an inspirational message of hope. But it always captures something much larger than itself — the spirit of a community, unified in its common feeling or cause, like the time a gay men's choir sang "Make Them Hear You" at a rally in Tennessee. Or the time counter protestors sang "This Little Light Of Mine" in Charlottesville, Va. to a group of white nationalists. On July 4, NPR kicks off its American Anthem series. It'll eventually feature 50 different anthems picked by NPR staffers, music scholars, artists and listeners. In anticipation of the series, we dedicate this week's episode of All Songs Considered to anthems. We're joined by NPR's Elizabeth Blair, producer of the American Anthem series, as we reflect on the soundtracks to our collective experiences.