Customary Law of the Sea is under great stress worldwide and needs U.S. support
The treaty would officially give U.S. fisherman priority over stocks adjacent to the American coast, and the U.S. Navy would continue to navigate the globe unimpeded. But the U.S., almost alone, has never ratified the treaty it sought and needed, despite the efforts of every President since, because the rule is so customary that it goes mostly unchallenged.
Those who oppose ratification believe that regardless of whether the U.S. is a part of it or not, the Treaty, in binding others, provides the ground rules the U.S. seeks generally and now needs in the Arctic. This is a delusion.
Without the U.S. ratification of the Treaty, which would greatly support its integrity, the agreed upon 200-mile zone deal is under great stress around the world. The South China Sea is a prime example where the 200-mile zone deal is threatened as China claims much more, and the Arctic Ocean will be another. The U.S. must be able to legitimately defend its interests; It could challenge the encroachment of others as a ratified member of the treaty.
Opponents of UNCLOS claim that the United States should not become a party because the United States already enjoys the benefits of UNCLOS through customary law and, therefore, should not unnecessarily incur the treaty's burdens. However, this ignores the fact that customary law can change and can also be influenced by how parties to UNCLOS decide to interpret its provisions.