By the second half of the 20th century, American popular music had become a dominant force in world culture. Many artists spoke out in song, harnessing the power of music to convey social dissatisfaction and political protest, and the civil rights movement and the politicization of the Baby Boomer generation during the Vietnam War propelled protest music to the heights of mainstream culture. In this chronicle in song, critics and singer/songwriters explain the phenomenon of protest music and recall its heady glory days.