Proliferation in recent years of a literature that seeks to examine the sources, content, and meanings of whiteness in American life stems from several factors. Among these are: (1) the sociology of academic trends; (2) the growth in recent decades of new academic specialties and interdisciplinary studies that accelerate the velocity of interpretive tendencies and problematiques; (3) reaction against a perceived retreat in civic and academic discussion, and national political life, during the 1980s and 1990s from acknowledgement of the historical and persisting force of racial stratification and inequality; and 4) the combination of atrophy of extramural Left politics and heightened perceptions of the political significance of academic debates. Most consequentially, as Professor Arnesen maintains, the turn to “whiteness studies” emerges from a version of the question crystallized more than a century ago by Werner Sombart, “Why is there no socialism in America?” The literature produced under this rubric is generally marred by conceptual ambiguities, ahistorical formulations, and lack of interpretive discipline. Particularly as it engages labor history and the work of labor historians, the whiteness literature is anchored in the hoary, and fundamentally miscast, debate over the centrality of racial versus class dynamics in shaping working-class experience and American politics.