Much of the debate over the difference slavery made in the United States has been framed by the work of Eugene Genovese, who has explained the South as a pre-modern, pre-capitalist region where dominant planter elites enveloped society, economy, and politics. "Planter hegemony" set the South apart and explained the inevitable war with the North over slavery. Genovese put the master-slave relationship at the center of his argument about the South, arguing that it determined class and social relations, as well as ideology, law, political expression, and nearly every facet of southern life. The South, according to Genovese, was sharply different from the North, but not so different from other pre-modern societies in history. (Genovese, Roll, Jordan, Roll; Genovese, "Yeoman Farmers"; Genovese, The Slaveholders' Dilemma)

James M. McPherson has also put slavery at the center of the conflict, the system "underlying all" of the differences between North and South. For McPherson, the North and South took divergent paths of economic development and their differences far outweighed their similarities. Slavery was at the heart of the difference between the sections, according to these scholars, but the difference it made was in the form of a fork in the road taken long ago. According to McPherson, the North's path was characterized by "heavy investment in social overhead capital, which transforms a localized subsistence economy into a nationally integrated market economy; rapid increases in output per capita, resulting from technological innovation and the shift from labor-intensive toward capital-intensive production; the accelerated growth of the industrial sector compared with other sectors of the economy; rapid urbanization, made possible by an increase in agricultural productivity that enables farmers to feed the growing cities; an expansion of education, literacy, and mass communications; a value system that emphasizes change rather than tradition; an evolution from the traditional, rural, village-oriented system of personal and kinship ties, in which status is 'ascriptive' (inherited), toward a fluid, cosmopolitan, impersonal, and pluralistic society, in which status is achieved by merit." (McPherson, Ordeal by Fire, 13)

Recently, McPherson put the difference between North and South in starker terms. The North, he argued, "hurtled forward eagerly toward a future of industrial-capitalism that many Southerners found distasteful if not frightening; the South remained proudly and even defiantly rooted in the past." The South fought, according to McPherson, to preserve its vision of what the Constitution protected--property, including slave property, and a citizenry "comprised of an independent gentry and yeomanry of the white race undisturbed by large cities, heartless factories, restless free workers, and class conflict." These generalizations have become widely accepted visions of how best to explain the coming of the Civil War. For the most part they confirm an inevitable conflict waged by opposing societies, one moving forward and the other moving backward. (McPherson, "Ante-bellum Southern Exceptionalism," 22)

The perspectives of Genovese and McPherson are based on broad statistical indices of modernity, such as aggregate rates of urbanization, industrial production, literacy, and the like. They rely on political language and travelers' accounts to flesh out their portrayals. Social science historians in the 1960s and 1970s who investigated the structural underpinnings of Northern and Southern society, however, found more similarities than differences between the sections. The American Historical Review offered a roundtable on the issue in 1980. There, Edward Pessen asked, "How different from each other were the antebellum North and South?" His answer was: not fundamentally different, especially if one focused on property distribution among whites. In fact, Pessen argued, North and South were not so much different as complementary, joined through mutual benefit in their economies and common social and political structures. He relied on a range of research, most notably Gavin Wright's and Lee Soltow's analysis of the basic similarities in wealth distribution and income between the sections. Pessen concluded that the North's and South's similarities might have more to do with the coming of the Civil War than their differences. He pointed to "similarly selfish interests--or perceived interests" rather than to "differences in their cultures and institutions" as the most compelling explanation for the Civil War. (Pessen, "How Different")

One participant in the forum, Stanley Engerman, noted that much of the scholarship Pessen reviewed examined only either the North or the South. Few works were explicitly comparative, testing the similarities and differences across the sections. Another participant, Thomas Alexander, concluded with a discouraging, if accurate, summary: "there is still little agreement on how all of these [factors] interacted to bring about an intersectional war, nor is there agreement on which of the similarities and differences are central to understanding antebellum life." That statement remains true more than twenty years later. (Alexander, "Antebellum North and South,")