In the timeline of American punk rock, hardcore came between the punk of the 1970s and 1990s grunge. Characterized by fast, loud and aggressive songs, minimal musicianship and violent behavior by the audience, it remained below the radar of the mainstream. In "American Hardcore: The History of American Punk Rock 1980-1986," Paul Rachman and Steven Blush document this short-lived scene by talking to just about everyone who contributed to it. Richard James Havis reports.