"Relatively easy"
not like the entire economy was destroyed and entire cities burned to the ground.
I think part of it is that the South got off relatively easy. Sure the war itself was horrible and bloody (so are all wars) but the Radical Republicans who wanted to go all Treaty-of-Versailles on the south didn't get their way. And despite this relative forgiveness, Confederate nationalism (which is really the right word for it in my opinion: if you are implying that there is a distinct southern heritage that was embodied in the Confederacy much more closely than in the United States, that's essentially a nationalism centered on the Confederacy), still remained strong and influential for a very long time.
I specifically went out of my way to address this ahead of time and I still get hit for it.
Yes, the war was and remained the bloodiest war in American history. But wars are like that. All wars are terrible. But so are some peaces, and the peace the Confederacy got was fairly mild all things considered. Yes, the period after is called the Reconstruction, but it was
Reconstruction, not, you know, leaving the South for dead or imposing a brand new order from on high. I mean given that the Radical Republicans in Congress were 1 vote shy of removing a President from office for preventing them from going to town on the South, I feel safe it calling it "relatively soft/easy/mild." Consider the alternatives...