As I said, the truth is the truth - Northerners DID have slavery and IT IS NEVER HINTED AT IN SCHOOL. The latter is the point of this article and of this discussion.
You're correct about the farmland in the upper mid-west by the time of the ACW; I'm still stuck on the original colonies from whence the slavery thing came. The East Coast northern region is rocky. Half of MD is rocky, and amazingly, THAT half of MD was more the northern sympathizers in the war (although, not by any means all).
Indeed the argument is not an excellent 1, but it does serve to put northerners and others in proper perspective, not as the perfect angels they're made out to be. (And as I stated very early, check out some old news about banning slavery in NJ in the 1830s - many of those Yankees weren't too happy about it!)