The slaves were definitely in second place. Lincoln’s prime goal was preserving the Union not freeing the slaves but slavery was still a key issue in the war. Decent men like Lee saw slavery for the great evil it was.
I personally take the view, in which the Southern States had a Right and Lincoln did not.
The Federal Government was not or is not Sovereign. It was a creation of the States. They exercised their sovereign authority, and voted with their feet as we should today.
JOHN TAYLOR of Caroline:
Sovereignty is the highest degree of political power, and the establishment of a form of government, the highest proof which can be given of its existence. The states could not have reserved any rights by the articles of their union, if they had not been sovereign, because they could have no rights, unless they flowed from that source. In the creation of the federal government, the states exercised the highest act of sovereignty, and they may, if they please, repeat the proof of their sovereignty, by its annihilation.
Good day