USNI News Western Pacific Pulse: Oct. 23, 2026

Exercise Keen Sword 27 is a U.S.-Japan military exercise. In the article, it places the Theodore Roosevelt Carrier Strike Group in the Philippine Sea with several allied and partner ships. The exercise matters because it brings different navies together in one operating formation.

The USS Theodore Roosevelt, carrying Carrier Air Wing 11, leads the group with USS Chosin. Japanese ships JS Ise, JS Kongo, and JS Asahi are also present. HMAS Stuart, HMCS Regina, and a French frigate complete the formation described.

As of Wednesday, these ships were operating in the Philippine Sea as part of the exercise. The excerpt does not describe particular drills or missions. Their combined presence shows a broad maritime partnership, while the exercise provides a setting for coordination among the participating navies.

The Philippine Sea lies in the western Pacific Ocean, broadly east of the Philippines and south of Japan. It is a large maritime space connected to important routes around East and Southeast Asia. The source identifies it as the operating area for Exercise Keen Sword 27.

That setting gives naval forces room to maneuver ships and aircraft while operating far from shore. The article describes eight warships there, including USS Theodore Roosevelt, USS Chosin, JS Ise, JS Kongo, and JS Asahi. Australian, Canadian, and French frigates are also included.

The sea’s position makes it relevant to exercises involving the United States, Japan, and other partners. The excerpt does not state specific training objectives or scenarios. In general, exercises in such open waters help navies practice communication, formation movements, and coordinated operations in a realistic regional environment.

The force described represents five countries: the United States, Japan, Australia, Canada, and France. It includes eight named or identified warships operating in the Philippine Sea for Keen Sword 27. This is a sizable multinational naval formation.

The ships are USS Theodore Roosevelt, USS Chosin, JS Ise, JS Kongo, JS Asahi, HMAS Stuart, HMCS Regina, and one French frigate. The group therefore includes an aircraft carrier, a cruiser, a Japanese helicopter destroyer, two Japanese destroyers, and three frigates.

The number shows the exercise is more than a bilateral encounter, even though Keen Sword 27 is identified as a U.S.-Japan exercise. Australia, Canada, and France add their own naval units. The excerpt does not give crew numbers, aircraft totals, or the French frigate’s name, so those figures cannot be counted here.

The ships alongside the United States and Japan represent Australia, Canada, and France. Australia sends HMAS Stuart, Canada sends HMCS Regina, and France contributes an unnamed frigate. Their presence expands the formation beyond the two countries named in the exercise title.

The article places these ships with USS Theodore Roosevelt, USS Chosin, JS Ise, JS Kongo, and JS Asahi. This creates a mixed naval group with different national crews, ship types, and command arrangements. Working together requires shared communications and agreed procedures.

Their participation shows that the exercise supports cooperation among a wider set of maritime partners. It does not prove that every country has the same role or objective. However, the multinational lineup demonstrates practical naval coordination and a willingness to operate together in the Philippine Sea.

A carrier strike group is a naval formation built around an aircraft carrier and supported by escorting warships. The carrier provides the central aviation capability, while cruisers and destroyers can help defend the formation and support its operations. The article identifies USS Theodore Roosevelt as the group’s leader.

The carrier is especially important because it carries Carrier Air Wing 11. Unlike a shore base, it can move across the sea while launching and recovering aircraft. USS Chosin and the other participating ships add protection, sensors, communications, and additional weapons to the formation.

This arrangement allows a navy to combine air and sea power in one mobile force. The excerpt does not state which aircraft or missions were used during Keen Sword 27. It does show the carrier operating with Japanese, Australian, Canadian, and French ships, making the group a multinational platform for coordinated maritime activity.

Large naval exercises let ships and aircraft practice operating as one force. Typical activities include air defense, surface surveillance, maritime patrol, formation movements, communications, replenishment, and responses to simulated threats. These skills matter because real operations require many units to share information quickly.

In this formation, USS Theodore Roosevelt provides Carrier Air Wing 11, while USS Chosin and the Japanese, Australian, Canadian, and French ships add escort and maritime capabilities. The key mechanism is coordination: units exchange information, follow common procedures, and synchronize movements through command networks.

The source does not identify specific maneuvers, aircraft missions, weapons events, or simulated threats during Keen Sword 27. Therefore, those activities should be understood as capabilities such a force can practice, not confirmed events from the excerpt. The multinational lineup indicates that interoperability is a central practical challenge and benefit.

Countries conduct multinational naval exercises to build trust, improve interoperability, and prepare forces to operate together. The Western Pacific matters because several allied and partner navies regularly work in the same broad region. Practicing together reduces confusion during a future crisis and strengthens shared procedures.

Keen Sword 27 illustrates this through a U.S.-Japan exercise joined by Australia, Canada, and France. USS Theodore Roosevelt and Carrier Air Wing 11 operate with USS Chosin and Japanese, Australian, Canadian, and French ships. The mechanism is repeated coordination among different crews, communications systems, commanders, and ship types.

That cooperation can support deterrence by demonstrating capability, unity, and readiness, although the excerpt does not state a specific adversary or threat. It also exposes coordination problems that partners can fix during training. Continued exercises may deepen practical alliance links, but the source gives no schedule or prediction beyond the reported activity.