Slavery had an overwhelming impact on the economy, politics, and society of the United States during the first sixty years of the nineteenth century. The most important effect was to divide American political culture into two increasingly irreconcilable factions until the differences exploded into a civil war.
While the United States remained an agrarian country during this period, the vast majority of the industrial development, or building of factories to turn raw materials into finished goods, took place in the north. Because of slavery, the southern states could base their wealth on growing and supplying raw materials, primarily cotton, which was then exported to England to be turned into cloth in the British mills. The region's economic dependence on slavery made it difficult for the south to abolish the institution because the plantations could not turn a profit without both a reliable labor supply (slaves cannot quit) and the almost nonexistent cost of a captive work force. However, at the start of the Civil War, the south was at a huge industrial disadvantage and knew it. It had no base for manufacturing weapons. It hoped that its superior military leadership and possibly the support of England, which depended on southern cotton supplies to keep its textile factories running, would lead to a quick victory.
Politically, slavery polarized people to the point it paralyzed the country, dominating everything from western expansion (would new states be free or slave?) to Supreme Court decisions. The publication of Harriet Beecher Stowe's Uncle Tom's Cabin led to a political firestorm, with groups opposing slavery demanding its immediate end, while slavery supporters increasingly demanded that it not just be tolerated as a necessary evil, but approved as a social good. The demand that one be either pro or con on slavery tore the country apart.
Socially, the south developed a hierarchical society based on race that was agrarian and atavistic while the north increasingly embraced industrialism, equalitarianism, and progress. The south celebrated the leisurely life of the southern aristocrat and his military prowess, while the north appreciated hard work and business ability. The increasing revulsion of many northerners at the social evil of one person owning another, coupled with the south's increasingly entrenched defensiveness of an untenable and morally indefensible social institution, ripped the country apart. Slavery was not a situation in which one could have just a lukewarm opinion, and, eventually, a war was required to resolve the conflict
