Everybody is half right. And each situation, is also unique despite looking sort of the same.
What was the world on the battlefield of Kurukshetra in India so long ago? Then, perhaps you could argue, to those then as two great armies faced off each, it was effectively the entire world.
When the Assyrians and Babylonians faced off, to them it was almost the entire world. There were no Christians or Muslims then.
The Egyptians and Hittites. One the famed Egyptian religion, another under Indo-Aryan traditions. Was that a religious struggle?
Humans have all sorts of reasons. Some like to blame religion, but this happens with or without religion. And each is also unique.
You give the government power, this is going to happen sooner or later, because the government is humans. I suspect some think they have a lot of great ideas. If they took charge, the one's who think they can implement their great ideas on everyone else, they will start the great wars. This forum would even start a great war - with each other perhaps - it is sort of expected almost. Gays are persecuted in many places of the world, though there is no better place for them then the West, America and Europe, yet it wouldn't surprise me if the Lesbians took Big Sister Power Government they would start the war on homosexual men, and the transvestites would be "put on the trains" as part of a purge to implement the "solution".
But the "Great War" never manages to kill everyone. Somehow humans survive. I really doubt there ever will be the "final" one. Even killing can be totally exhausting, and it isn't as easy as some think, bomb or no bomb.
I like what I am seeing with the "Arab League". What were some thinking or expecting to happen? It is obvious, Iran wants to take over the entire region, and no one is stopping Iran from getting the nuke. So Saudi Arabia, is suppose to NOT do the obvious? They will now want - and start developing - the nuke in response. Because Iran was allowed to "carry on".
I am not so sure this is just the old Sunni verse Shia thing. ISIS is Sunni, and they want to attack the Arab League also.
Maybe the Arab League represents something else, neither Sunni nor Shia. Maybe it is saying, "the rest of you guys are nuts and we are not going to let you guys 'solve the problems'". A lot of bad deals. And actually a lot of modern factors here. Hell if I have a solution, and typically I mistrust most "solutions". Obama sure ***** up the cafeteria. God I wish he was never born. It might have been better. Government - pzzzzzzzuuggggg. Jimmy Cater sucked. He still does. Socialism sucks. Caused a lot of this. Also I wouldn't call this latest, a "civil war". When the communist Vietnamese (government) and the socialist Khmer Rouge Cambodians (government) attacked each other, I didn't call that "civil war".
I hope the Arab League with their new flag smashes both the Sunni ISIS and the Shia Iranian mullah power grab and their nuke program. Both are leprosy. The only part of this that has me worried big time is the Pakistani element - that could flip either way real easy.
And it was in Pakistan, the North West Frontier Province of what was formerly India, that this modern Islamic extremist terror thing all started in the first place late 1800s.