Western Pacific Defense Demonstrated by 16-Day Training of Kaga and George Washington in 2026

The U.S. aircraft carrier George Washington, which departed from Yokosuka, has entered Guam. Behind this seemingly mundane port news, the Japan Maritime Self-Defense Force's escort ships Kaga, Fuyuzuki, and Shiranuhi have been conducting training with the carrier strike group in the Western Pacific from May 22 to June 16. According to the announcement by the Maritime Staff Office on June 17, air defense, anti-submarine warfare, surface warfare, LINKEX, cross-deck operations, and underway replenishment were conducted collectively. This is not merely a goodwill training exercise, but a practical training to share the same operational rhythm between Japan and the U.S. outside the first island chain.

Significance of Kaga Operating Alongside the Carrier Strike Group

The escort ship Kaga is the second ship of the Izumo class and has undergone phased modifications with the operation of F-35B in mind. Although the announcement does not specifically indicate fixed-wing aircraft operations, it is significant that multiple domain tactical training was conducted in the same maritime area as George Washington, Robert Smalls, Benfold, Shoup, and the replenishment ship Earl Warren. In other words, Kaga is being tested not only for its future role as a light aircraft carrier but also as a connector ship for communications, replenishment, anti-submarine, and air defense at this point in time.

In my view, the focus of this training is not on the size of the ship names. Rather, it lies in scenarios where Shiranuhi and Shoup simultaneously receive underway replenishment from U.S. supply ships. How naturally can ammunition, fuel, aircraft maintenance, and personnel exchanges be handled? If a crisis in the Taiwan Strait or the southwestern islands prolongs, what will be decisive is not the firepower on the first day, but the ability to continue moving forces on the fourth, seventh, and fourteenth days.

Training with USCGC Midgett in Sagami Bay

The announcement from the Maritime Staff Office on June 18 revealed that on June 17, an SH-60K conducted deck landings and in-flight refueling with the U.S. Coast Guard cutter Midgett in Sagami Bay. Midgett is a Legend-class national security cutter and is not a naval vessel. However, this reflects the recent changes in Japan-U.S. cooperation.

In the field around the Senkaku Islands and the southwestern islands, it is not necessarily destroyers or escort ships that first come to the forefront. The Coast Guard, Japan Coast Guard, patrol aircraft, and rotary-wing aircraft gather information at the boundary between peacetime and crisis, gauging the intentions of the other party. If the SH-60K can refuel from a U.S. Coast Guard vessel, then the JMSDF's patrol helicopters can maintain surveillance for a longer period. This is not flashy deterrence, but it is extremely practical for gray zone responses.

Connection to Valiant Shield

According to the U.S. Pacific Fleet and USNI News, the George Washington strike group departed Yokosuka on May 23 and arrived in Guam on June 16. It is highly likely to become a core part of Valiant Shield 2026. This exercise will utilize a wide air and maritime area around the Japanese mainland, Guam, and Hawaii, and it is expected that the Typhon medium-range missile system and HIMARS will be deployed at Kanoya Air Base. Typhon is a ground-launched system capable of operating SM-6 and Tomahawk, equipment that blurs the boundary between maritime warfare and land-based firepower.

In this context, the training of Kaga in the Western Pacific, the training with Midgett in Sagami Bay, and the deployment of Typhon at Kanoya are not separate news items. Escort ships, carrier strike groups, Coast Guard, and ground-launched missiles are beginning to be placed on the same operational map. During the Cold War, the JMSDF was primarily an expert in sea lane defense. In 2026, the JMSDF is involved in the issue of where to stop the approach of the adversary, in addition to sea lane defense, integrating land, sea, and air operations.

Strengthening Deterrence and Remaining Weaknesses

As the activities of the Chinese Navy expand into the East China Sea, Western Pacific, and the Sea of Japan, the fact that Japan and the U.S. conducted air defense, anti-submarine, surface, communication, and replenishment operations over 16 days in the Western Pacific is a clear advancement in capability. However, as capabilities increase, the burden of political explanation also grows. Regarding the Typhon and HIMARS at Kanoya, it has been explained that live-fire exercises will not be conducted, but from a local perspective, the boundary between temporary deployment and normalization is not easily visible.

The deterrent power of the alliance is influenced not only by the speed of bringing in equipment but also by the speed at which society accepts it.

It is welcome that Kaga can operate alongside the carrier strike group. However, the true challenge lies not in the connectivity of the fleet but in whether the speed of judgment among the government, local authorities, residents, and allied forces can be aligned when a crisis prolongs. At sea, replenishment can be trained. Political supply lines have not yet been sufficiently trained.

Major Information Sources

• Japan Maritime Self-Defense Force, Japan-U.S. Bilateral Exercise, June 17, 2026
• Japan Maritime Self-Defense Force, Japan-U.S. Bilateral Exercise with USCG, June 18, 2026
• U.S. Pacific Fleet, George Washington Carrier Strike Group arrives in Guam, June 16, 2026
• USNI News, George Washington Carrier Strike Group in Guam for First Port Call of Spring Patrol, June 17, 2026
• Stars and Stripes, US Army sending Typhon missile systems to southern Japan for upcoming drills, June 16, 2026