For virtually all people there is a universal principle that could unite us if only we all turned our attention to it.
Even among people who vehemently oppose each other, there is an unrecognized commonality.
For some of us it is just an instinctive moral understanding and others it is a more intellectualized principle. But for all of us who accept morality at all, it is an undeniable moral truth.
The Nations Of Sanity project identifies this moral truth as the concept of self-ownership and the Non-Aggression Principle.
The concept of self-ownership is simply the idea that everyone has right (and responsibility) over only their own self. The Non-Aggression Principle is simply the self-evident moral principle that comes from this concept. If everyone has right over only their own self and not over others then it is objectively immoral to violate that right.
This means that any violation of self-ownership is an initiation of force against peaceful people and any force used against such aggression would be, by definition, justified and defensive force.
If we simply follow the logical progression it becomes undeniable that the NAP (Non-Aggression Principle) provides us an objective definition of crime, which gives us a universal standard for law.
So, it seems undeniable that the NAP should be established as the universal law, or terms of peace, between all people.
Also, because ruling people is a violation of self-ownership, therefore a violation of the NAP, we cannot establish this principle as law through a ruling authority, because ruling authorities would be illegal under such a law. Therefore, the only way to establish the NAP as the law without contradiction is to establish it as the terms of a universal peace agreement.
In addition to this, the Nations Of Sanity, recognizes that a peace agreement would need to encompass 3 dimensions of agreement for real world application. We need first the basic agreement, to establish this principle as the universal law or "terms of peace". Then we need to properly define the limits of tolerance over differing interpretations and then we need to ratify rightful ownership (again, based on this principle).
And that's basically it. That is the elephant in the room that we just need to draw people's attention to. Because if we can unite on this very basic moral principle then we can all live in peace, regardless of our other differences, and if we cannot unite on this basic principle then we are fucked.