For what it's worth, while I think Battle Cry is the greatest single volume work of history I've ever read, I think it really earns its money in these early chapters. It's very hard to read those pages and come away thinking the war wasn't actually caused by slavery. The most shocking portion to me was when MacPherson didn't simply make the case about secession, but detailed how planters were actually plotting to erect a tropical empire based on slavery stretching into South America and beyond. That whole section will give you a cold chill, because I think it correctly outlines what was at stake. 

One request from people interested in this discussion, please don't make the following comment: "I haven't read Battle Cry of Freedom but what you really should read is XXXX." It's not so much that it's wrong, it's that we have Civil War threads aplenty. Let this one be about what it's supposed to be about. We know you are smart. You no longer have to prove it.

Let's go.