In 1975, I was the navigator and salvage diving officer on the USCGC Polar Star north of Alaska. To support polar research in the Chuckchi Sea (where offshore drilling may soon take place), we broke through thick ice for weeks.

The multi-year thick ice is almost gone now and much has changed since then. Indeed, the only constant is that the Arctic has surprised us again and again. The ice not only has retreated faster than any model predicted, but also surprisingly was found to provide an important environment to certain fish populations. Storms unexpectedly become more powerful as the seas open up, too. And although the Arctic appears bigger as ice retreats, the prospect of more shipping through the opened channels makes the Bering Straits appear smaller. Global leaders must expect that we (and they) will continue to be surprised. So what are the ground rules necessary for navigating both the realities of a new Arctic, and the surprises ahead?

The United States faced similar territorial questions for all oceans after the Second World War, and it pursued difficult multilateral negotiations over three decades to protect the country's economic and strategic interests.

The central deal — which has still not been ratified by the U.S., though it is exactly what the U.S. sought — established that each country has rights to oil and fishing up to 200 miles off of the coast, though the traditional rights of navigation of those waters remain available to all other states.

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.

It is critical for the U.S. to remember that Alaska spans only eight percent of the Arctic circumference, while Russia reaches across 44 percent. Russia has 3 million people above the Arctic Circle; the U.S., perhaps 20,000. Russia has four major river basins flowing into the Arctic; the U.S., none.

So how will the Arctic Ocean be governed? In large measure, the question goes back to how the five Arctic coastal states govern their respective ocean zones and work together to make the division of resources and conservation efforts effective for themselves and each other. And for the U.S. to have the voice it needs in the Arctic, it must ratify the Law of the Sea Treaty.

David D. Caron, the dean of the Dickson Poon School of Law at King's College London, formerly co-directed the Law of the Sea Institute at the University of California, Berkeley.