Live-MINEX26 Begins Around Iwo Jima: Japan-U.S. Mine Countermeasure Training with 8 Vessels Supports Southwest Defense

Around Iwo Jima, mine sweepers search for mines, while U.S. Navy EOD personnel coordinate underwater disposal procedures. The Live-MINEX26, announced by the Maritime Staff Office on June 9, is a joint Japan-U.S. mine warfare training exercise taking place from June 15 to 27. The participating Japan Maritime Self-Defense Force (JMSDF) units include 2 mine warfare mother ships, 2 mine sweepers, 3 mine sweep boats, and 1 FFM, totaling 8 vessels. The U.S. side will dispatch a team from the 5th Explosive Ordnance Disposal Mobile Unit, specifically EODMU5.

There are no flashy missile launches or images of aircraft carrier decks. However, in my view, this announcement holds more practical significance for understanding this week's southwest defense than Typhon or F-35B. To move a fleet along the first island chain, it is essential to first clear the shipping routes.

Continuity Demonstrated by the 53rd Live Mine Disposal

According to the announcement materials, the training activities this time include mine sweeping, clearance operations, mine searching, and EOD. The JMSDF has been conducting live mine disposal training since 1972, and this marks the 53rd time. It is also noted as the 6th Live Mine Countermeasures Exercise with the U.S. Navy. While this number may seem small, training with live ammunition involves significant burdens related to location, sea conditions, fishing regulations, and safety management, making the continuity itself a capability.

In the Ise Bay MINEX in February, the JMSDF deployed 1 mine warfare mother ship, 2 mine sweepers, 12 mine sweep boats, 1 MCH-101, and an EOD team, while the U.S. side participated with EODMU5 and UUV operators. The shift of the location from Ise Bay to the area around Iwo Jima can be seen as a move to expand the focus from port protection to opening shipping routes in the open sea and along island chains.

The Significance of the Participation of 1 FFM

Notably, the participation of 1 FFM is significant. The Mogami-class escort ship is built as a multi-functional escort vessel and is designed to handle mine warfare missions. However, it cannot immediately replace the operational experience of specialized mine warfare vessels. Mine sweeping involves not only sensor performance but also a craftsmanship-like ability to read seabed topography, tidal currents, and acoustic conditions.

The U.S. Pacific Fleet explained that during the February MINEX 1JA, Japan-U.S. forces conducted training to open shipping routes through simulated minefields, jointly commanding UUV operations, mine sweeping, clearance, and mine neutralization. The current Live-MINEX26 strongly emphasizes aligning the procedures of EODMU5 and the JMSDF mine warfare units in real maritime environments.

Comparison with China's Mine Warfare Capabilities

Yasuhiro Kawakami of the Sasakawa Peace Foundation analyzes that the Chinese Navy's mine sweeping and clearance-related vessels outnumber those of Japan and the U.S. in quantity, and they are rapidly closing the gap with the introduction of USVs and UUVs. On the other hand, Japan has accumulated operational experience through post-war domestic mine disposal, the Korean War, and the 1991 Persian Gulf deployment. This experience is difficult to replicate in a short period.

The issue is that the superiority of experience does not always compensate for a lack of vessel numbers. As the Chinese fleet increases its activities around the southwestern islands from the east of Taiwan, the JMSDF's mine warfare units must simultaneously be aware of Japan's main ports, the southwestern islands, and U.S. military support routes. The geographical scope of their missions is clearly expanding.

The Silence on the Map Around Iwo Jima

The area around Iwo Jima does not attract political attention like the southwestern islands. However, it is located on the operational line connecting the Japanese mainland, the Marianas, and the Philippine Sea. It is a maritime area where anti-submarine patrols, resupply, air deployment, and fleet maneuvers intersect, making it a natural location for mine warfare training.

Mines are inexpensive weapons that can consume a fleet's time. A fleet deprived of time loses its initiative, even if it has a numerical advantage.

In recent years, Japan has garnered interest in its "shooting capabilities" such as the Type 12 surface-to-ship guided missile, Typhon, and F-35B. However, without the ability to maintain shipping routes, utilize ports, and return damaged vessels before shooting, deterrence exists only on paper. The understated nature of Live-MINEX26 rather highlights this essence.

Remaining Weaknesses

The announcement did not provide details on the UUVs, mine sweeping equipment, or command and communication systems to be used. While this is a natural secrecy, it makes capability assessment difficult from an external perspective. Particularly as the U.S. Navy reduces dedicated mine warfare vessels and transitions to unmanned systems and the LCS class, expectations on the Japanese side may increase.

The true weakness of southwest defense is not just the lack of missile range. It is how politics and joint operations can recover the 24 hours lost due to a single mine. The mine sweeping units are the first to confront that question, and Live-MINEX26 should be seen as a quiet rehearsal for that.

Sources

• Japan Maritime Self-Defense Force, Live-MINEX26 announcement, June 9, 2026.
• Japan Maritime Self-Defense Force, Mine Warfare Exercise Ise Bay announcement, January 20, 2026.
• U.S. Pacific Fleet, Mine Warfare Exercise 1JA 2026 completion release, February 10, 2026.
• Sasakawa Peace Foundation, analysis of Japan, U.S. and China mine countermeasures capabilities.
• USNI News, Japan minelaying drills around the Sakishima Islands, October 7, 2025.