You said "The American Civil War was[n't] fought over slavery."

It, in fact, was.

Now you're saying that the Union didn't go to war to free the slaves. Hey, idiot. The south struck first, at Fort Sumter. It was the South who was the aggressor, and they WERE fighting it over slavery.

Thus, the North went in to quell the rebellion and found a convenient moral argument in anti-slavery.

Slavery was at the core of every aspect of the civil war.