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The United Nations Convention on the Law of the Sea was completed in December 1982 and is now ready for ratification. This Treaty may not ultimately enter into force. But, since it was arrived at by consensus, the Treaty is bound to influence or indeed come to represent customary international law. In fact, the Treaty is already cited by the International Court of Justice. Thus, how it will affect U.S. submarine operations should be understood, even though the United States (along with a very few other states) elected not to be a party to the Treaty. And, by reviewing the history of the law of the sea, it can be speculated as to the effect of the new Treaty on u.s. submarines.

Necessarily, what follows is a simplification — a layman’s perspective– and should not be regarded as authoritative.

Prior to World War II there were, essentially, two legally defined parts of the seas: the High Seas and the Territorial Sea. Because of the Truman Proclamations of 1945, the 1958 Conventions on the seas included two other sea areas — the Continental Shelf and what is now termed the exclusive “Economic Zone,” which involves fishing and conservation of the living resources in this sea area. The 1982 Convention then added two more spheres of interest, one for Straits and the other for the “Area” of the seabed beyond the limits of national jurisdiction, i.e., the floor of the High Seas. For submariners, only the High Seas, the Territorial Sea, and the Straits areas are of particular concern.

The High Seas

The High Seas are all parts of the seas outside of the Territorial Sea or bodies of waters within states. There is no sovereignty over any part of the High Seas, but vessels using the High Seas are sovereign territory of the flag they fly. Among the traditional high seas freedoms are the freedoms of navigation and overflight. “Freedom of navigation” has historically included the right of submerged movement of submarines.

The creation of an “exclusive” Economic Zone out to 200 nautical miles from a coastal state -by the 1982 Treaty — involves about one-third of the high seas but does not affect the freedom of navigation. It remains to be seen, however, whether some coastal states will attempt to encroach on freedom of navigation by expanding, or attempting to expand, their jurisdiction in this exclusive economic zone.

The Territorial Sea

In the Territorial Sea the coastal state has all but absolute sovereignty. It is in effect an extension of the land itself. The right of passage of foreign vessels within another state’s territorial sea is restricted to “innocent passage,” which, for submarines, means that when in another’s territorial sea they must travel on the surface and display their own flag.

Sovereignty over a territorial sea is universally accepted in international law. However, the breadth of the territorial sea has resisted legal definition. The earliest limits used the range of an 18th Century cannon to measure the breadth of the territorial sea. This was gradually equated to one marine league or 3 nautical miles. On November 8, 1793, the United States adopted the 3-mile limit. It is fair to say that the 3-mile limit was generally, though not universally, accepted up to about World War II.

The 1958 Convention on the Territorial Sea did not set a limit on the Territorial Sea. But it did recognize a “Contiguous Zone,” not to extend beyond 12 miles from tbe coast. In this zone, a coastal state could take measures to prevent or punish infringements of its customs, fiscal, immigration or sanitary laws and regulations within the territorial sea. Thus it is a type of “hot pursuit” zone or buffer zone, into which a nation’s jurisdiction extends for these purposes.

In 1960 the Soviet Union set the breadth of its territorial sea at 12 miles. By 1979, 76 nations claimed or accepted 12 miles, and 25 more recognized limits beyond 12 miles. Only 23 states, including the United States, recognized miles.

In any event, the 1982 Treaty set the breadth or the territorial sea as 12 nautical miles, and continued the requirement for surface navigation or submarines while in the territorial sea. The Treaty also extended the contiguous/hot pursuit zone to 24 nautical miles, or 12 miles beyond the territorial sea.

But what of passage in straits? With a 12mile li~t, reportedly some 116 straits may lawfully be territorialized and available to foreign submarines only under the limited right of innocent passage– i.e., transit on the surface.

The present treaty, however, purports to take care or that with a new straits regime and its concept or “transit passage.”

Straits Used in International Navigation

Prior to 1982 there was a general recognition in international law that transit through straits connecting portions of the high seas was a right of any nation. Special treaties, of course, governed the passage through certain straits, e.g. the Turkish strait, the Danish strait, the Strait of Magellan. Significantly, no treaty covers the Strait of Gibraltar. The United States — for straits greater than 6 miles in breadth — could always claim a “high seas” component in the strait with its attendant “freedom of navigation,” i.e., submerged right of transit. The 1982 Treaty, to compensate for a 12-mile territorial sea limit at the same time preserved the right of passage through straits used in international navigation by establishing a new regime defined as “transit passage.”

The 1982 Treaty recognizes four types of straits:

  1. Straits whose passage has been regulated by long-standing international conventions in force, like the Turkish, Danish and Magellan straits, where it was deemed better to continue the existing legal agreements than to apply new rules.
  2. Straits which can be transited by remaining in the High Seas area at all times. In such corridors, high seas freedom of navigation persists.
  3. Straits which are used for international navigation between one part of the high sea or an exclusive economic zone and another part of the high seas or an exclusive economic zone. These “straits” compose a great bulk of straits used in international navigation. For such straits “transit passage” implies the rights of freedom of navigation and overflight, solely for the purpose of continuous and expeditious passage. Any rererence to surrace navigation by submarines are omitted while a carefully worded subsection of the Treaty only calls upon ships in “transit passage” to rerrain rrom activities other than those incident to their normal modes of expeditious transit.

The use or the words “freedom of navigation” in the definition of “transit passage,” and a “normal mode” provision, form the basis for the right or submerged transit by submarines of straits used for international navigation.

The carrying out or any research or survey activities during transit passage is prohibited without the prior authorization of the States bordering straits. Strait states may designate sea lanes and traffic separation schemes where necessary and may adopt laws and regulations relating to transit passage in respect to pollution control, fishing, etc.. Such regulations must not however hamper or suspend the right of transit passage. Strait states must give appropriate publicity to any danger to navigation or overflight within or over the strait.

4. The fourth category of straits have no right of “transit passage.” Submarines have only the right of “non-suspendable innocent passage,” i.e., surface transit. Such straits are the “island exception” straits, where the waters of the strait lie between the mainland and an island of a single state, and an equally convenient route exists seaward of the island. An example is the Strait of Messina, between the Italian mainland and Sicily. Since ships can easily go around Sicily in high seas waters, the conference felt that there was no need to preserve more than a right of non-suspendable innocent passage through such a strait. Similarly, only innocent passage applies to straits connecting the high seas to a territorial sea.

In the development of the 1982 Treaty, Spain and a group of strait States tried to amend the text to require surface transit of submarines -evidence that opposing states understood that the text permits submerged transit. It seems clear that the 12-mile limit and the transit passage provisions go hand in hand and that the United States, the Soviet Union, or the other maritime nations would never have agreed to one without the other.

It is this author’s view that the present Law of the Sea Treaty compensates for the expansion of territorial sea limits by providing special rules for straits that preserve the traditional high seas freedom of navigation for most straits that connect the high seas.

So What?

While this writer personally regrets the u.s. decision not to sign the Treaty, the fact is, that it does not seem that dire consequences will follow. The 12-mile limit is now customary international law and in practice the U.S. observes it. Since the rights of “transit passage” are given to “all states,” the u.s. benefits from the Treaty’s rules despite not being a party to the Treaty. In addition, the rights and duties of innocent passage are probably an improvement over previous conventions. With the Soviet Union and other maritime nations insisting on adherence to the new straits regime, the u.s. will benefit. In the event of selective discrimination by littoral states against the U.S., the U.S. can still argue for the right of freedom of navigation based on traditional practice. Practically, most of the strait states either lack the capability to detect submerged submarines, or, if friendly, tend to ignore such transits — in contrast to overflights.

What the United States does give up is the availability of a forum in which to vindicate its rights. The Treaty’s dispute-resolution mechanisms include compulsory third party adjudication, conciliation procedures, etc., available only to, and between, States who are parties to the Treaty. So what happens if Spain or Morocco, who acceded to the straits rules as defined in the Treaty, now say to the u.s., “Why should I let you transit what are now my territorial waters when you, the United States, have not accepted the other obligations of the Treaty?” For such a case, the u.s. may have to resort to the use of the threat of force to insure passage of its ships or aircraft.

In summary, while there is likely to be only limited immediate effect from U.S. nonparticipation in the Treaty — as a matter of law — the u.s. has traded certainty for continuing uncertainty, and has excluded itself from the mechanisms available to resolve the uncertainties.


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