“[thing that clearly exists] doesn’t exist” is established code for “is not the crisp category you think it is” (e.g. Why Fish Don’t Exist).
Additionally, the definition of murder might vary from place to place, but if there isn’t a crisp definition for a given jurisdiction, we say that place lacks law and order. And since treaties are definitionally between multiple parties, those parties need to share a definition of anything material, in a way they don’t need to share a definition of murder that occurs on their own soil.
“[thing that clearly exists] doesn’t exist” is established code for “is not the crisp category you think it is” (e.g. Why Fish Don’t Exist).
Additionally, the definition of murder might vary from place to place, but if there isn’t a crisp definition for a given jurisdiction, we say that place lacks law and order. And since treaties are definitionally between multiple parties, those parties need to share a definition of anything material, in a way they don’t need to share a definition of murder that occurs on their own soil.