When the U.S. Constitution was written in 1787, however, the interests of slaveholders and those who profited from slavery could not be ignored. Although slaves could not vote, white Southerners argued that slave labor contributed greatly to the nation's wealth. The Constitution therefore gave representation in the Congress and the electoral college for 3/5ths of every slave (the 3/5ths clause). The clause gave the South a role in the national government far greater than representation based on its free population alone would have given it. The Constitution also provided for a fugitive slave law and made 1807 the earliest year that Congress could act to end the importation of slaves from Africa.
The Constitution left many questions about slavery unanswered, in particular, the question of slavery's status in any new territory acquired by the U.S. The failure to deal forthrightly and comprehensively with slavery in the Constitution guaranteed future conflict over the issue. All realistic hope that slavery might eventually die out in the South ended when world demand for cotton exploded in the early 1800s. By 1840, cotton produced in the American South earned more money than all other U.S. exports combined. White Southerners came to believe that cotton could be grown on with slave labor. Over time, many took for granted that their prosperity, even their way of life, was inseparable from Africa slavery.For more than 80 years, people in the Northern and Southern states had been debating the issues that ultimately led to war: economic policies and practices, cultural values, the extent and reach of the Federal government, and, most importantly, the role of slavery within American society.