In the 1980s I participated as a lecturer in a training course on marine sciences for the island states of the South Pacific. The competence of the trainee participants impressed me greatly. The reservoir of trained scientists in these island mini-states is minuscule, and some of the men and women at the training course, who had left high school and college just a few years back, were already in positions of public decision making. Now they were preparing themselves to negotiate as representatives of their countries with the most powerful country on earth (the United States of America) about fishing zones and exclusive fishing rights.
The position of the USA at the time was that the regulations of the Law of the Sea on fishing do not apply to migratory species (fish that do not stay in the fishing area of a single country but roam the world ocean) and that as a consequence every nation has the right to fish for tuna and similar species anywhere, including the waters of the island states. The island states argued that the convention on fishing zones applied to all living marine resources.
Obviously, a century ago the island states would not have had a chance to defend their position. The framework of international law and the scientific training of their own young negotiators changed that situation.