Key advantage of U.S. ratification of UNCLOS is in reinforcing foreign perspectives on our naval rights
One of our most important objectives in seeking a universally ratified Law of the Sea Convention is to put a stop to the erosion of high seas freedoms in coastal areas that characterized the development of customary international law in the twentieth century. There is no reason to believe this erosion will not continue in the absence of a treaty restraint. In my opinion, the most plausible way to block the gradual erosion of high seas freedoms in the exclusive economic zone, and its eventual transformation into something much more like a territorial sea, is a widely ratified Law of the Sea Convention to which the United States is party, and with respect to which the voice and practice of the United States are prominent authoritative evidence of what the Convention means.
For operational planners, the essential question is not what we think our rights are, but what foreign governments think. We need the greatest possible influence over the perception of foreign governments regarding the source, legitimacy, and content of their obligations to respect our high seas freedoms, especially in their exclusive economic zones. We achieve that best by becoming party to the Convention. The alternatives are likely to be both less effective and more costly.