[Sen is right - this war has a large OOC motivation. There's also an IC motivation; just pick what suits you best :-)
Regarding OOC:
Vannaka talks a lot about roleplay. In fact most PoC members get the IC/OOC separation right; however, they neglected that roleplay is about having fun together, even if you're on opposite sides. I wouldn't mind making Elvors unhappy, provided a great story unfolds from that. And "great" means I can tell it to friend and they want to hear the end. Don't think roleplay as a football match, think of it as a theatre play, where the actors and the audience are one and the same.
So, if you need to kill a weak character for IC reason, talk to him OOC and ask him for his or her consent. If that's impossible due to lack of time, at least send an apology afterwards - and get their consent for the next time.
If you just kill, you're not generating great stories, you're generating unhappy players.
Remember: PlaneShift is intended to be fun to play. Yes, that includes other players, and yes, this even includes clueless players.
Well, these are the OOC reasons for the war.
For the OOC aspects, I think number of players on each side is more important than which side guild-yields.
Now for the IC aspects:
We're similar to many crusader orders. We try to help people, but lacking an effective investigative police force and methods, we're forced to work on hearsay and thin evidence. Somebody drew a line between PoC and Camp Banished, there was nothing that contradicted that line, so we simply assume the line is real and act on that assumption.
So don't insist on watertight evidence. It is not necessary to have such a thing to start a war.
Maybe the next war will be based on assumptions that all players know are wrong, but the characters don't. This could become part of a great story.]