Sovereignty Limited by International Law and Treaties

This Court notes and appreciates the ferocity and passion by which petitioners stressed their arguments on this issue. However, while sovereignty has traditionally been deemed absolute and all-encompassing on the domestic level, it is however subject to restrictions and limitations voluntarily agreed to by the Philippines, expressly or impliedly, as a member of the family of nations. Unquestionably, the Constitution did not envision a hermit-type isolation of the country from the rest of the world. In its Declaration of Principles and State Policies, the Constitution "adopts the generally accepted principles of international law as part of the law of the land, and adheres to the policy of peace, equality, justice, freedom, cooperation and amity, with all nations." 43 By the doctrine of incorporation, the country is bound by generally accepted principles of international law, which are considered to be automatically part of our own laws. 44 One of the oldest and most fundamental rules in international law is pacta sunt servanda — international agreements must be performed in good faith. "A treaty engagement is not a mere moral obligation but creates a legally binding obligation on the parties . . . A state which has contracted valid international obligations is bound to make in its legislations such modifications as may be necessary to ensure the fulfillment of the obligations undertaken." 45

By their inherent nature, treaties really limit or restrict the absoluteness of sovereignty. By their voluntary act, nations may surrender some aspects of their state power in exchange for greater benefits granted by or derived from a convention or pact. After all, states, like individuals, live with coequals, and in pursuit of mutually covenanted objectives and benefits, they also commonly agree to limit the exercise of their otherwise absolute rights. Thus, treaties have been used to record agreements between States concerning such widely diverse matters as, for example, the lease of naval bases, the sale or cession of territory, the termination of war, the regulation of conduct of hostilities, the formation of alliances, the regulation of commercial relations, the settling of claims, the laying down of rules governing conduct in peace and the establishment of international organizations. 46 The sovereignty of a state therefore cannot in fact and in reality be considered absolute. Certain restrictions enter into the picture: (1) limitations imposed by the very nature of membership in the family of nations and (2) limitations imposed by treaty stipulations. As aptly put by John F. Kennedy, "Today, no nation can build its destiny alone. The age of self-sufficient nationalism is over. The age of interdependence is here." 47