Trilateral Security Cooperation: Act Now Against Sea Mines

By Commanders John F. Bradford and Daniel E. Fillion, U.S. Navy

MCM Trilateral Cooperation: Don’t Wait

The DPRK mine threat is high, and a response would consume exceptional time and resources. According to James FitzSimmonds of the U.S. Naval War College, “Among all the naval warfare areas, the mine versus MCM competition might represent the most radical warfighting asymmetry and the most disproportionate offense-defense cost-exchange ratio.” 1 In fact, between 1945 and 2001, sea mines have seriously damaged or sunk almost four times more U.S. Navy ships than all other means of attack combined. 2

The DPRK found mines to be extremely effective during the Korean War, and the cash-strapped regime continues to rely on its inventory of as many as 50,000 mines as force multipliers easily employed against alliance operations dependent on open sea lanes. 3 DPRK mines threaten ports in ROK and along Japan’s west coast, including Sasebo, home to significant U.S. and Japanese surface forces. Mines also could enable the DPRK to influence the tempo of combat and deter opposing forces from using amphibious landings to bypass battle lines ashore.

In a situation short of war, the DPRK might deploy sea mines as a provocation or an escalation tool. Recent provocations include the 2010 clandestine torpedoing of the ROKS Cheonan and the 2015 use of land mines to attack ROK soldiers. Voicing his concern that sea mines could easily disrupt trade and culpability could be difficult to prove, retired ROK Navy Vice Admiral Jung Ho-sub writes, “Even a single mine, if planted by the North, could create a serious crisis situation with a significant impact on almost all aspects of ROK society.” 4

Once mines have been deployed, MCM operations are the only option to restore waters for safe navigation. In an open conflict, there also could be opportunities to interrupt the DPRK mine-deployment sequence, but it would be unwise to rely on such disruption as the only avenue. Therefore, a capable MCM force is of paramount importance. Japan, the United States, and the ROK all maintain MCM assets in or near the Korean theater, but cooperation mostly has been limited to activities that improve readiness within the bilateral alliances.

Bilateral approaches are insufficient, however, because neither of the two alliances has sufficient capacity to respond effectively to the DPRK mine threat. Therefore, the three nations should commit to advancing greater MCM cooperative capacity. Ideally, the three navies could respond as a combined defensive force working across borders. A less ideal, but more feasible, construct is one in which Japan and South Korea coordinate their activities while operating in separate waters. Harmonizing these activities would require additional confidence-building and the development of new coordination mechanisms.

The ROK Navy only has ten MCM ships, and not all are capable of clearing mines. The U.S. Navy has 11 MCM ships, but only the four forward deployed to Sasebo are based in the Pacific. The United States also maintains three MH-53E airborne MCM helicopters in ROK, and U.S. expeditionary systems are available. Nonetheless, the scale and scope of the threat likely will exceed the U.S. Navy-ROK Navy capacity to quickly open maritime approaches to the peninsula or to contain the threat to the waters immediately around Korea.

Of the three nations, Japan has the most MCM forces. It possesses 27 MCM clearance and auxiliary ships and is the only nation other than the United States to possess an airborne MCM capability. Coupling this large force with the modern technology systems and highly skilled sailors, the Japan Maritime Self-Defense Force (JMSDF) has earned its reputation as perhaps possessing the world’s best MCM force. The Japanese also have experience, albeit dated, clearing mines in Korean waters during the Korean War. 5

From a political perspective, MCM cooperation is relatively low cost. MCM resources are single-purpose and nonescalatory. MCM ships, aircraft, and explosive ordnance demolition (EOD) teams cannot be repurposed as offensive forces—they have no weapons other than those used for close-quarters defense. At the task force level, their command and control also is separate from forces that conduct combat operations. Furthermore, their operations happen at sea, so training requires no boots on the ground. If necessary, planning meetings can take place under way or in low-sensitivity locations such as Guam or Hawaii. Thus, while expanding trilateral MCM training may trigger Chinese strategic anxieties or encounter domestic political resistance, concerns could be more easily managed than those arising from security cooperation in other areas.

In terms of financial and operational costs, trilateral MCM cooperation also need not be expensive. Because the bulk of the three nations’ forces are within a few hundred nautical miles of one another, near the primary training ranges and the key waters where they would operate in crisis, training would not require huge investments in time or fuel. Additional synergies could be found by reoriented existing unilateral and bilateral exercises to include new partners and more realistic scenarios without placing new demands on individual units.

Opportunities for MCM Cooperation

Boosting trilateral security cooperation is not a new recommendation—senior defense leaders have been saying this for years, and MCM cooperation has been mentioned specifically. 6 Political leaders must establish trilateral MCM cooperation as a priority and encourage military leaders to move ahead. The authority to plan and execute trilateral training should be delegated to the lowest possible level, ideally to the fleet commanders. Cooperation should focus on fostering interoperability and developing the coordination mechanisms that would enable unity of effort in a crisis. There already are many venues for efficiently facilitating this cooperation.

The JMSDF hosts annual MCM events with the U.S. Navy, which ROK Navy officers have observed. More recently, the JMSDF has opened the door to full participation by ROK Navy MCM forces. The ROK Navy should seize these opportunities, and Japan should continue to send invitations, even if they sometimes are declined. This would advance five goals:

• Boost trilateral interoperability at the unit level

• Lay the foundations for trilateral coordination structures

• Identify the best roles and missions for the three forces in a crisis

• Display the prowess and professionalism of the three MCM forces

• Message to the international community that the threat from the DPRK is driving greater trilateral cooperation

The ROK Navy also should invite the JMSDF to observe and participate in its MCM training events. The annual MCM Symposium and Clear Horizon exercise, which includes U.N. Command sending state navies, should be opened to the JMSDF. In the past, one of the sticking points has been the display of the JMSDF ensign—the same flag flown by the Imperial Japanese Navy—by ships moored in ROK ports. This should not be a showstopper; workarounds have been found to enable JMSDF ships to participate in events such as the 2008 International Fleet Review and a 2010 Proliferation Security Initiative exercise, both held in Busan. Even if Japanese ships and aircraft cannot participate, the involvement of JMSDF officers in the symposium would be a meaningful step forward.

The U.S. Navy should consider the Korean theater as a proving ground for its most advanced capabilities, such as unmanned vessels. Exercising these systems in the locations where they may be employed provides operators valuable exposure to hydrographic conditions. It also gives them an opportunity to command these systems in a coalition context in a simulated contested environment—the type where experts believe unmanned systems will be the most effective. 7 Funding to get these relatively new systems to theater for training should be prioritized to make future employments more effective and more cost efficient.

Finally, the MCM forces of the U.S. Navy, ROK Navy, and JMSDF should look at ways to participate trilaterally within or on the sidelines of existing multinational exercises. The trilateral BMD training that has taken place in tandem with Rim of the Pacific (RimPac) exercises exemplifies how this could be done. Hawaii might be far for the three services to send MCM ships, but all should dedicate some sort of MCM forces to RimPac 2018. All three also should commit vessels to the Western Pacific Naval Symposium MCM exercise to be hosted by Australia in 2018. As these ships would leave from nearby ports and follow similar voyage plans, they should conduct cooperative training and personnel exchanges throughout the transit. Other exercises in the Middle East, Europe, and the United States might provide similar opportunities, and the U.S. Navy should make sure the ROK Navy and JMSDF are invited. Finally, the allies should consider opening historically bilateral exercises (e.g., Keen Sword and Foal Eagle) to trilateral MCM forces. In these events, MCM units should serve as trailblazers and test cases to help advance other types of training when appropriate.

Advancing trilateral cooperation in the face of an expanding DPRK threat is overdue. Political challenges should be compartmentalized and greater focus should be placed on areas of military cooperation essential to these nations’ and our defenses. MCM is an area where it should be easy to move ahead if leaders seize the initiative. MCM likely will be of vital importance in a crisis, and Northeast Asia currently is unready to respond. Success in this high-value, low-cost cooperative endeavor also may strengthen relationships and facilitate advancement of trilateral security cooperation in other areas.


1. James FitzSimmonds, “Cultural Barriers to Implementing a Competitive Strategy,” in Thomas Mahnken ed., Competitive Strategies for the 21st Century: Theory, History, and Practice (Palo Alto, CA: Stanford University Press, 2012), 296.

2. Scott Truver, “Taking Mines Seriously,” Naval War College Review (Spring 2012), 32.

3. Sydney Freedberg Jr, “Sowing the Sea with Fire: The Threat of Sea Mines,” Breaking Defense, 30 March 2015.

4. Jung Ho-Sub, “ROK-US-Japan Naval Cooperation in the Korean Peninsula Area: Prospects for Multilateral Security Cooperation,” International Journal of Korean Studies 16, no. 1, 202.

5. James Auer, The Postwar Rearmament of Japanese Maritime Forces, 1945-71 (Praeger, 1973), 64–66.

6 See for example Yoji Koda, “The Emerging Republic of Korea Navy: A Japanese Perspective,” Naval War College Review (2010), 30-1 and Jung, “ROK-US-Japan Naval Cooperation,” 201–2.

7. Scott Savitz, “Rethink Mine Countermeasures,” U.S. Naval Institute Proceedings 134, no. 7 (July 2017), 56–60.

Commander Bradford is a conducting studies and research at the Japanese National Institute of Defense Studies in Tokyo. In his previous Navy assignment, he served as regional cooperation coordinator for the Seventh Fleet. He studied in Indonesia and Singapore as an Olmsted Scholar.

Commander Fillion is the assistant chief of staff for security cooperation (N7) at U.S. Naval Forces Korea. His previous assignment was at the Joint Staff as the Japan desk director (J5), and as the Chairman of the Joint Chief’s lead travel planner in the Chairman’s Action Group. He studied in Japan as an Olmsted Scholar.




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