Maybe - but I'm tired of red vs blue, as are a lot of the playerbase.
I'd rather see Horde Sin'dorei in Quel'Thalas fight back against hostile (neutral-by accounts), Amani Trolls wielding the Void.
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But all accounts, law and order is well established within Silvermoon, so the chances of a civil war are all but reduced.
Their were more chances of a civil war, during the TBC era than now. Just like in Draenei society with the Broken and regular Draenei.
The evidence is within the recent Eastern Kingdoms Novel.
And if the Sunwell is corrupted (probably by Azshara), then the Sin'dorei will band together and use the resources that they know about. I don't mind the Sunwell being lost, if it means that the Sin'dorei remain in Silvermoon and Quel'Thalas and those places change to indicate that this is a place full of Blood and Arcane Magic and Fel Magic is once again, wildly used.