Security cooperation among the United States, Japan and South Korea is taking shape beyond the threats facing the Korean Peninsula and its immediate surroundings. The Freedom Edge exercise planned off Jeju Island and South Korea's preparations to send military assets to the Strait of Hormuz reflect this transformation in two different theaters.
Trilateral security cooperation expands
The Freedom Edge exercise, which the United States, Japan and South Korea plan to hold off Jeju Island from September 7 to 11, demonstrates the operational dimension of the three countries' security commitments. The scope of the exercises has gradually expanded since the security framework was established at Camp David in 2023.
This year's exercise is described as the most advanced demonstration of trilateral cooperation to date. Its significance stems not only from its scale but also from its role in placing security coordination among the three countries on a more permanent and operational footing.
Preparations for Hormuz
South Korea is preparing to send a P-8A Poseidon maritime patrol aircraft, a logistics support ship and a Navy explosive ordnance disposal team to the Strait of Hormuz. Contacts on the mission's scope and port access are continuing, while a final decision has not yet been made and any potential deployment will be submitted to parliament for approval.
The planned mission is expected to focus on maritime surveillance, logistical support and navigational safety rather than direct combat engagement. This approach could allow South Korea to present its presence in the region as a contribution to the safety of maritime transport rather than participation in a war.
South Korea has six P-8A Poseidon aircraft in its inventory, acquired primarily to monitor North Korean submarine activity. Sending some of the aircraft to the Persian Gulf could mean sharing capabilities normally assigned to Seoul's primary area of operations.
Energy security and alliance pressure
More than 60 percent of South Korea's crude oil imports pass through the Strait of Hormuz. Maintaining uninterrupted navigation through the strait is therefore important to the country's energy security.
South Korea's preparations for Hormuz, however, cannot be explained solely by energy security. The acceleration of the preparations after messages from Washington linking Seoul's position on Iran to the future of military cooperation raises the question of how alliance relations are affecting the decision.
Washington's changing expectations
The burden-sharing Washington expects from its Asian allies is expanding beyond the allocation of more resources to their own defense to include taking on responsibilities outside their immediate security environments.
Japan appears to have undergone this transformation earlier and more visibly. Japanese Prime Minister Sanae Takaichi's linking of a possible intervention over Taiwan to her country's survival marks an important threshold in Tokyo's postwar security outlook. Japan, however, can take a more cautious position on sending warships to the Strait of Hormuz by pointing to its constitutional and legal limitations.
The absence of a similar constitutional restriction in South Korea, combined with the requirement for parliamentary approval of any potential deployment, could make Seoul more receptive to Washington's demands beyond the region. Economic ties with China, parliamentary approval and domestic perceptions of security, however, determine the limits of that openness.
The search for strategic autonomy
Support for nuclear armament in South Korea has reportedly reached approximately two-thirds. This indicates that more autonomous deterrence options are also finding social support while security ties with the United States remain in place.
The emerging structure is seen less as a new military alliance in the traditional sense than as a security network deepening through interoperability and taking on a stronger maritime character. Considering the Korean Peninsula, the Taiwan Strait and the Strait of Hormuz along the same strategic line shows that regional security calculations are becoming increasingly interconnected.
In the coming period, it will be important to see whether exercises such as Freedom Edge expand from missile defense and North Korea-focused scenarios toward protecting maritime transport routes. The differing responses of Japan and South Korea to this expansion, along with uncertainties surrounding the future of the US security guarantee, are among the main factors that could shape the allies' pursuit of strategic autonomy.
