The primary sources in this unit concern three mine explosions that ripped through the southern Colorado coalfields in the early twentieth century. The first learning goal is to analyze these sources so to better understand the centrality of coal, coal mining, and mine disasters to class conflict and political struggle in early-twentieth-century America. Next, use your exposure to the devastating human costs of coal-powered industrialization to ask and answer questions like these: What misgivings about the costs of industrialization did these disasters reveal? What solutions did contemporaries propose to the shockingly high fatality rates in U.S. coalfields? Were mine disasters inevitable consequences of industrialization, or could they have been avoided? What can these contending views of mine safety teach about the urgent campaigns for government regulation and unionization that shaped politics during the Progressive Era?