Gavin Wright argues in his book Slavery and American Economic Development that the United States contained two relatively distinct property systems in the North and the South prior to the abolition of slavery. The two were of course linked through a variety of financial and institutional mechanisms but were nonetheless different. Wright further argues (but does not fully develop the point) that the political bodies and what I would call the dominant class fractions associated with each property system maintained what was effectively a cold war throughout the early 19th century. This cold war obviously became a hot war in 1861 with the outbreak of the civil war. This was not the first heating up, however. The American Civil War was preceded by the experience known as “Bleeding Kansas” and the famous raid on Harper’s Ferry. Arguably, the resistance of enslaved people, aided by free blacks and other abolitionists, formed smaller instances of a north-south hot war earlier, or at least formed instances of southern internal instability tied to external forces and which threatened to spill over into war. I can’t prove this but I suspect that the federal government throughout this era was both a field of contest between northern and southern forces as well as a mechanism (and a group) with the function (and the interest) of keeping the two systems and sets of constituencies tied in to the same country. Insistence on the need to preserve the union was a longstanding impulse that pre-dated the Lincoln administration.