Save your breath. The neo-Confederates here are adamant that the Civil War had nothing to do with slavery, and anyone who disputes their historical revisionism is ignorant, stupid, dishonest, or all three. Kind of like how Obama and Kerry are convinced ISIS has nothing to do with Islam.
What ever you think, war broke out because of the Union invasion of Virginia. War was initiated by Lincoln on April 16-17 with his declaration of blockade of the South.
So,did the Union invade to stop slavery? Not even Burns makes that assertion.