But, in a move of treachery, he began to send in reinforcements. Ft. Sumter was a foreign occupation of troops of sovereign Confederate land. Jeff Davis was merely evicting the foreign occupational forces.
It only cost the lives of 620,000 men, countless others physically-maimed, mentally-shattered, and addicted to Morphine, it destroyed the South, and forced the 14th Amendment on us that forced Federalism and gave us the misinterpretation that we now call anchor babies.
Had there been no Civil War and had Abe Lincoln left the CSA to its own devises, it has been speculated that the USA could have blocked them from Westward expansion; slavery would have been phased out, probably before the end of the 1860, or early 1870s, the USA could have refused to do trade with them and eventually frozen them out until they decided to come back to the US for favorable trade, and possible readmission to the US. However, something like that would not have been nearly as exciting as a hot war and mass destruction.