Enforcing this would be the real challenge, a delicate and ungrateful task, bordering on the impossible: the constant diplomatic and military effort will mostly be a discouraging endless chore, dismissed at best as helpless whiteknighting anyway.
However, it might prove fruitful in time, as such pact/ convention/ treaty would at least help give shape and tone to all Dual Universe organizations, by self-labeling those who openly sport it and those who disregard it. Communication, more than strength of arms, would be the key here.
Therefore, though neutral observers of the galaxy's colonization, D.U. Sleepers would be very willing to associate themselves with this initiative and help promoting it. Steve, Vulture Corporation and/ or anybody willing to lead along this windy uneven-stoned path can get in touch with me anytime.
(May I suggest the acronym "P.E.A.C.E." [Promotion of Ethics for Arcology, Citizentry and Ecosphere] ?)