"The shocking assassination of a major rival to UMWA president Tony Boyle catalyzed groundbreaking reform in the coal mining industry. In the early hours of New Year's Eve 1969, in the small soft-coal mining borough of Clarksville, Pennsylvania, longtime trade union insider Joseph "Jock" Yablonski and his wife and daughter were brutally murdered in their old stone farmhouse. Seven months earlier, Yablonski had announced his campaign to oust the corrupt...