Yes, I know. :) Isn't going to stop me from trying. 

But, one dinner later, and I'm starting to get things a little better. This magic that caused such a disastrous effect is new, right? Kind of like how, now that we know that the atomic bomb is a thing, a WWIII would pretty much obliterate everything? The children are gone, people are dying, and if the fighting continues after the cease-fire necessary for both sides to heal, it is likely that the weapon, or, more accurately, an adapted and narrower targeting version of that weapon, would be used again. The leaders of each side would see this, and know that if they started fighting, ever again, not only might it alert the humans, but it would likely cause the complete obliteration of one side, or both, depending on who it was that created the new magic. Since no one knows, except for the person who set it off, neither side would be willing to risk it, since it might belong to the opposing side. 

But that isn't going to stop the Daywalkers and NIghtwalkers from fighting. So they make the Organization the "bad guys," because they punish both/all members who participate in violent activity, not just the "victims". With neither side coming out on top, everyone just hates the Organization, and there is peace. At least, so long as both sides are balanced in power.