What cultural, social and/or economic difference between the North and South that would lead to greater tensions by the end of the 1850s? Did this make Lincoln’s election in 1860 the inevitable “final straw” for the dissolving of the United States?

What cultural, social and/or economic difference between the North and South that would lead to greater tensions by the end of the 1850s? Did this make Lincoln’s election in 1860 the inevitable “final straw” for the dissolving of the United States?