The thing is it's actually not inevitable. I suggest you read "How Civil Wars Start and How to Stop Them," which is about exactly what it says it's about.
I'm not necessarily thinking about just civil wars, although that is what the meme is about.
People are divided in more ways than just political view points. There's a growing inequality that could potentially lead to a revolution of sorts, if people are willing. I can think of a handful of other issues that might lead to similar outcomes.
I appreciate the recommendation though, I'll try to give it a read at some point.