Have to agree with this. Definitely not "ZERO". But then again, it was certainly not the only major issue behind succession and the war. It was one of a number. Pay attention to history, or you're doomed to repeat it.
I pay attention to history, but it gets repeated anyway.
What they usually say is, “This time it’s different.”
A lot of wasted young lives to end something that would gave ended likely peacefully at some point not far off.