[fungoking]

Agreed that there were multiple reasons on both sides.
What gets left out is the role of politics. If Lincoln had said the war was for freeing the slaves, how many northern white mothers and fathers would have sent their sons to die for black freedom?
Likewise, if the south had said this is a war to keep slavery, how many poor white southerners would have gone and fought to keep something they couldn't afford to have?
Like they said, “rich mans war, poor man's fight.”

[TBP]

There were multiple reasons on both sides, and both sides were both right and wrong.