So the South's motivation for starting the war in the first place is irrelevant? Good to know.
Your argument has descended to strawman repetition. You keep asserting that the South started the war, which is a point in dispute, and you keep asserting that SLAVERY justifies the North Invading, though you tediously refuse to show any connection between slavery and the invasion.
Yet you are the one claiming that the Union was motivated by slavery.
I am the one that is beginning to realize you won't remember what I actually said, and will instead insist on beating up on a straw man version of what I said.
I said the Union went to war to protect their income stream, (European Trade) which happened to be the result mostly of slave labor, and also to prevent the creation of competition in the form of European trade patronizing Southern ports.
The two things together would likely have constituted a billion dollar loss to the Northern Economy when total GDP for the year was 4.5 billion.
My explanation fits the available facts better than does yours. I don't have to try to explain a Union objective of the war of which no one seemed to be aware for the first 18 months. My theory doesn't require time travel.