Revisit Incidents at Sea

Dr. Richard Moss, PhD.

In addition to a number of colorful phrases and the curt dismissal of allegations that Russia interfered in the November 2016 U.S. election as “collective madness,” Russian Federation Deputy Foreign Minister Sergei Ryabkov told Japanese and Chinese media on 23 August 2017 that there is room to refresh agreements. Ryabkov mentioned INCSEA as one example. [i]

Similarly, in 2016, the chairman of the Duma (Russian parliament) defense committee and ex-commander of the Black Sea Fleet, Admiral Vladimir Komoyedov, told Russia-based Interfax that the bilateral arrangement failed to specify “the distance of approach, nor the distance of departure to avoid interfering with one another, and so on.” [ii]

Komoyedov’s statement reflects Russia’s—and its predecessor, the Soviet Union’s—position that the superpowers should specify fixed distances for encounters on or over the high seas. The U.S. Navy opposed fixed distances in negotiating the original agreement and still opposes fixed distances, insisting that ship and aircraft conduct be in accordance with the International Rules of the Road.

The Backstory on INCSEA

Previous episodes of détente—a lessening of tensions—began with incremental efforts. For example, Richard Nixon supported the ratification of the Nuclear Non-Proliferation Treaty (NNPT), which had been negotiated and signed by the Lyndon Johnson administration, even though the Soviet Red Army had crushed the Prague Spring several months before Nixon’s electoral victory. The Nixon administration’s early push for the ratification of the NNPT proved to be a tangible sign to Moscow that Nixon was serious about improving relations and arms control.

As with the NNPT, the seeds planted during the Johnson Administration for INCSEA finally blossomed and bore fruit during the Nixon Administration. According to David F. Winkler in Cold War At Sea: High Seas Confrontation between the United States and the Soviet Union (Naval Institute Press, 2000), the United States proposed bilateral talks in 1968, after several collisions, unsafe flybys, and accidents involving U.S. and Soviet ships and planes . Winkler attributed the incidents to the Soviet naval buildup—engineered by Fleet Admiral Sergei Gorshkov—after the 1962 Cuban Missile Crisis, U.S. involvement in Vietnam, and the concomitant proximity of U.S. and Soviet ships.

The Soviet Union accepted the proposal in late 1970, and the two sides held two rounds of talks. The first round took place in Moscow in October 1971, the same week that Moscow and Washington announced that Nixon would travel to the Soviet Union in late May 1972 for a superpower summit. The second round took place Washington, D.C., in May 1972, days before President Nixon and his entourage departed for the summit.

U.S. Secretary of the Navy John Warner and Soviet Admiral Gorshkov signed the agreement on 25 May 1972, in Moscow. [iii] One of nearly a dozen agreements signed at the summit, INCSEA was overshadowed by prominent arms control achievements, including the Anti-Ballistic Missile Treaty and the Interim Agreement on the Limitation of Strategic Arms.

It is ironic that one of the instruments governing interactions at sea and in the air between the American and Russian navies was shoehorned into the Moscow Summit. The agreement was only possible because the Soviets acquiesced to the U.S. position that the agreement be limited to general conduct formulations instead of specifying distances for naval and aerial intercepts, with the promise that the issue could be revisited.

In the end, INCSEA specified that both Soviet and U.S. warships would adhere to the 1958 Geneva Convention on the High Seas, and that U.S. and Soviet ships would avoid different types of harassment, such as shining spotlights on each other’s bridges and also the threatening gesture of simulated attacks. [iv]  Moreover, the agreement made provisions for the adherence to standardized signals and communication and specified measures to avoid hindering operations, such as carrier flight operations. In Washington, D.C., in May 1973, the U.S. and Soviet governments extended the INCSEA provisions to cover non-military ships. [v]

After bumping, or shouldering, incidents in the Black Sea in 1988, when U.S. Navy ships tried to exercise the right of innocent passage in Soviet territorial waters, Moscow and Washington negotiated the Uniform Interpretation of the Rules of International Law Governing Innocent Passage . Although related more to the United Nations Convention on the Law of the Sea than to INCSEA, the Uniform Interpretation did not resolve the inherent conflict between fixed distances and general conduct. In fact, the issue remains unresolved 45 years after the original agreement was signed.

Although there have been breaks of several years, the Americans and the Russians still meet regularly—as recently as July 2017 at Newport, Rhode Island—to review the INCSEA agreement and discuss violations. [vi]

The Path Ahead

While INCSEA improved the interactions of the U.S. and Russian navies, there is still work to be done.

Since Russia’s involvement in Ukraine and Syria, Russian attack aircraft have engaged in several unsafe, low-altitude flybys of U.S. warships operating in the Baltic and Black seas. In November 2017, a Russian Su-30 fighter conducted an unsafe intercept and came within 50 feet of a U.S. P-8A Poseidon flying in international airspace over the Black Sea. (Some reports said this intercept was as close as five feet.)   In April 2016, a pair of Russian Su-24s buzzed the USS Donald Cook (DDG-75) on multiple low-altitude passes and provided the perfect opportunity for photographic and video documentation . In February 2017, a pair of Su-24s, an Il-38 surveillance aircraft, and a separate Su-24 made low-altitude passes on the USS Porter (DDG-78) in the Black Sea. One of the Su-24s flew within 200 yards of the ship, flying at 300 feet at more than 500 knots, according to USNI News .

The Russians are not alone in aerial intercepts. In June 2017, NATO F-16 fighters were scrambled over the Baltic Sea to check three Russian planes, including two fighter jets that did not respond to air-traffic control. It turned out that one plane was carrying Russian Defense Minister Sergei Shoigu, who was en route to Russia’s heavily fortified exclave in Kaliningrad.

Perhaps the time has come to specify fixed distances for air-to-ship and air-to-air intercepts over the high seas. Fixed distances could help avoid ambiguity in situations where the intent of the parties—particularly, with respect to the use of force—cannot be readily identified. The Standing Rules of Engagement (SROE) for U.S. forces not only authorize but obligate ship commanders to exercise self-defense in response to a hostile act or demonstrated hostile intent . [vii] Intent can be difficult to gauge in the heat of the moment. At what point do deck-level, high-speed passes by attack aircraft become a demonstration of hostile intent?

Foremost, 2017 is not 1972 in terms of military and technological capabilities. With technological developments, planes and ships do not need to be physically close to surveil each other. Distances are easy to measure with radar, GPS, and computers. With the ready availability of high-resolution cameras and video recorders, it is easier to document infractions today than it was almost a half century ago.

There are several avenues available to refresh INCSEA. The existing mechanisms for annual meetings could present the opportunity to revise the agreement, or possibly upgrade it to the status of a treaty (which would require ratification by the Senate). [viii] The United States also could use its position, both with Russia and within NATO, to expand the number of bilateral agreements —or facilitate a multi-lateral agreement—establishing codes of conduct between Russian and NATO forces operating on the high seas.

The United States and Russia are not the only countries involved in air-to-air, surface-to-surface, and air-to-surface encounters. Perhaps a revised INCSEA could be synchronized with other existing agreements. For example, the United States and the People’s Republic of China have the Code for Unplanned Encounters at Sea (CUES), a non-binding agreement that regulates interactions. [ix] Similarly, Russia and Japan have an agreement on the prevention of incidents at sea outside territorial waters and in the airspace above it, which was signed in 1993, and revised over the last two years. [x]

There are also some potential roadblocks to implementing a revised INCSEA, first the stipulations in the 2014 U.S. National Defense Authorization Act, which forbid military-to-military cooperation between the U.S. and Russian militaries as a consequence of Russia’s misadventures in Ukraine. Any revised agreement also would need to be consistent with international law, to include the 1982 United Nations Convention on the Law of the Sea. Although the United States never has ratified the agreement, the United States considers those provisions of the treaty addressing navigation and overflight rights as being reflective of customary international law. [xi]

As Russian Federation President Vladimir Putin seems to include in his regular talking points (with varying degrees of enthusiasm), both Moscow and Washington are wont to pursue their national interests. Likewise, President Donald Trump talks about putting the United States first, and that the leaders of other countries need to and should put their countries first. That means to have any substantive improvement in relations, both sides should identify areas of mutual benefit.

Any revisions to INCSEA require both Washington and Moscow to agree that it is in each power’s interests. Thus far, the statements from Deputy Foreign Minister Ryabkov and other Russian leaders suggest they wish to discuss fixed distances. Maybe such revisions could help avoid close flybys, such as those the Donald Cook and the Porter experienced. Such revisions also would build off other success stories in the military-to-military realm, such as the 1989 Agreement on the Prevention of Dangerous Military Activities and the 2002 Open Skies Treaty .

Of course, there is still room for U.S.-Russian relations to worsen. With sanctions in place over Russia’s seizure of the Crimea, support for secessionist parts of eastern Ukraine, enabling Bashar al-Assad’s murderous regime, and interference in the U.S. election process, a further decline is certainly plausible.

Regardless of which direction U.S.-Russian relations go, incremental steps to improve what President Nixon called the “structure of peace” would be a good step in the international arena.

[i] Vladimir Isachenkov, Associated Press; August 23, 2017;  “Russian official says US and Russia aren’t in new Cold War”; Washington Post online:

[ii] .

[iii] U.S. Department of State, “Agreement Between the Government of The United States of America and the Government of The Union of Soviet Socialist Republics on the Prevention of Incidents On and Over the High Seas,” . See also: “Recently Concluded and In-Progress Negotiations and Agreements Between the U.S. and U.S.S.R.,” Richard Nixon Presidential Library and Museum (RNPLM), NSC Files, President’s Trip Files, SALT File, Moscow Summit [1 of 1] [Part 1 of 3], Box 496.

[iv] The “Convention on the International Regulations for Preventing Collisions at Sea (COLREGs),” often referred to as the “Rules of the Road,” was signed in October 1972—after INCSEA—and became the standard to which the United States and Soviet Union adhered beyond the 1958 Geneva Convention on the High Seas. See: International Maritime Organization, COLREGs,

[vi] U.S. Naval Forces Europe-Africa/U.S. 6th Fleet Public Affairs ,July 26, 2017, “US Navy Statement on INCSEA,”

[viii] U.S. Department of State, “Treaty vs. Executive Agreement,”

[x] Government of the Russian Federation, May 27, 2017, “On the approval by the Russian side of the draft Protocol between the Governments of Russia and Japan on Amendments to the Agreement on the Prevention of Incidents at Sea and in Airspace,”

[xi] United States Oceans Policy, March 10, 1983, .

Dr. Moss is an associate research professor, co-director of the Halsey Bravo research effort, and a faculty affiliate in the Russian Maritime Studies Institute at the U.S. Naval War College's Center for Naval Warfare Studies. He specializes in U.S.-Soviet relations during the Cold War and is an expert on the Nixon presidential recordings. He is the author of Nixon's Back Channel to Moscow: Confidential Diplomacy and Detente , published in January 2017. The ideas expressed in this article are his personal ideas and not reflective of U.S. Navy or DOD policy.





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