The 1803 Louisiana Purchase—by which the U.S. acquired more slaveholding territory in the name of national expansion—set off the dynamic that led to the Civil War. The United States has declined every opportunity to let the South go its own way; in return, the South has effectively awarded itself a big say in the nation’s affairs.
The South was the country’s aberrant region—wayward, backward, benighted—but it was at last going to join properly in the national project: that was the liberal rhetoric that accompanied the civil-rights movement. It was also the rhetoric that accompanied Reconstruction, which was premised on full citizenship for the former slaves. Within a decade, the South had raised the price of enforcement so high that the country threw in the towel and allowed the region to maintain a separate system of racial segregation and subjugation. For almost a century, the country wound up granting the conquered South very generous terms.
Nicholas Lemann, “The Price of Union”, The New Yorker (2 November 2015), 90.