The international relations theorist Hans Morgenthau considers power politics a reference rule. Natural law is a subjective law. Whoever exercises it can bend it to their advantage. However, nations must succeed in transcending themselves and exercising control over their choices. The dynamic of history demonstrates the interdependence of the world to the point of constituting an interdependence between nations. To the extent that any disruption of the international balance threatens humanity, all nations feel committed. States of the same geopolitical group have ended up coming together, and, more and more, a third-party state interferes with a conflict that is none of its business: peace is in crisis. International institutions have considerably fostered this rapprochement of the rules of conduct of states, making rules that transcend national law, guaranteeing international peace and conflict prevention.
States owe one another several legal and moral obligations. They also have to respect the freedoms and sovereignty of their people. They cannot wage wars amongst themselves in the name of their inalienable right to self-defense or to put themselves in defense of their people. In our society, all states have a leader, and this leader, to whom the people give their powers to act in their name, embodies the state and the principles and rules that govern relations between states. It is through such actions that the state applies international and national law. Of course, this formulation seems to ignore the great powers of the earth because they do not always act in the “state interest” sense, which I have alluded to.