'Participation in Design' Required in the Face of Theater Strategy Encompassing Wartime Operational Control, Nuclear Deterrence, and Trade

The Indo-Pacific is Not an 'Option' but a 'Designed Theater'

The recently released U.S. National Defense Strategy clearly illustrates the extent of Washington's shift in perspective regarding the Indo-Pacific.

In this strategy, the U.S. designated China not as a short-term threat, but as the sole 'pacing challenge' defining the U.S. military's force structure and theater operations.

This signifies that the Indo-Pacific strategy is no longer merely one of diplomatic options, but has become the benchmark governing U.S. military operations and alliance structures for decades to come.

The core of the U.S. National Defense Strategy is theater-centric thinking.

The 'theater' referred to here signifies a strategic operational space that encompasses not only defense against a specific country but also force employment, conditions for intervention, and escalation management.

The U.S. military is no longer a force for automatic defense; it is operated as mobile assets maximizing strategic effects within the theater.

Alliances are also redefined not as objects of protection, but as entities sharing roles and responsibilities. Instead of automatic intervention and abstract deterrence, conditions, choices, and pre-design are moving to the center of strategy.

USFK and Wartime Operational Control: The Theater is Already in Operation

This change is no exception for the Korean Peninsula. The U.S. Forces Korea (USFK) already functions as forward-deployed, fixed assets within the Indo-Pacific theater, beyond just responding to North Korea.

The missile warning system, intelligence and reconnaissance integration, and the normalization of ROK-U.S.-Japan security cooperation demonstrate that the Korean Peninsula is not an independent defense space but operates as part of a theater where China, Russia, and North Korea intersect.

At this juncture, the discussion on the transfer of wartime operational control (OPCON) takes on an entirely different meaning.

While OPCON is often explained as the recovery of military sovereignty, within a theater-centric strategy, OPCON is less a symbol of command authority and more a mechanism for clearly assigning accountability.

The more OPCON is transferred to South Korea, the more the primary responsibility for the defense of the Korean Peninsula rests with the ROK military, and U.S. military intervention shifts from automatic protection to the realm of strategic choice.

This does not signify a weakening of the alliance, but it demonstrates that the way the alliance operates is fundamentally changing.

The Merger of Security and Trade: The Theater is Not Driven Solely by Military Means

A particularly noteworthy aspect of the U.S. National Defense Strategy is the integration of security and trade. The United States treats trade, industry, and supply chains not as external factors separate from the military domain, but as critical elements for sustaining the war effort.

Semiconductors, batteries, shipbuilding, energy, and critical minerals, while trade items during peacetime, are transitioned into elements of theater strategy during crises.

Tariffs and export controls no longer function as trade policy but as security instruments.

Participating in the Indo-Pacific strategy means sharing theater responsibilities not only in military cooperation but also in industrial and trade sectors.

Theater participation implies a structure where security costs and economic costs are incurred simultaneously.

The U.S. Intent is 'Participation in Design,' Not 'Protection'

Amidst these structural changes, the U.S. intent is relatively clear.

In explaining the goals of its Indo-Pacific strategy, the U.S. National Defense Strategy states, "We will set the military conditions so that no one, including China, can dominate the United States or its allies, and thereby maintain the balance of power in the Indo-Pacific."

This is less a promise to automatically defend a specific country and more a declaration of intent to design the conditions for deterrence at the theater level.

Simultaneously, the U.S. has clarified the changing role of its allies.

The National Defense Strategy states, "We will urge major regional allies and partners to take on greater responsibility for collective defense and enable them to do so," formalizing the sharing of responsibilities among allies.

Indeed, USFK is operated not as a force for automatic defense but as an Indo-Pacific theater asset, and the transfer of OPCON is also being pursued based on the premise of condition-based responsibility sharing.

Furthermore, the U.S.'s diplomatic and trade posture, linking cost-sharing for defense and cooperation in industry and supply chains, clearly demonstrates a direction toward maintaining alliance protection while distributing its costs and choices.

The United States does not want to lose South Korea. However, it also does not wish to make an exception for South Korea.

In a theater being reshaped with China as the benchmark, South Korea is an indispensable key ally, but it is not a beneficiary guaranteed the privilege of automatic protection.

What the United States requires is not a declaration of loyalty, but an answer as to whether South Korea is prepared to participate in the design of the theater.

Both 'Participation Without Authority' and 'Ambiguous Neutrality' Are Dangerous

In particular, South Korea's ambiguous stance on the North Korean nuclear issue reveals its limitations.

The U.S. National Defense Strategy views North Korea's nuclear use not as a mere regional incident but as an issue that fundamentally changes the nature of the entire theater.

Nevertheless, if South Korea is unable to substantially participate in the process of setting red lines for nuclear deterrence and managing escalation, the transfer of wartime operational control may remain an transfer of responsibility and risk, rather than an enhancement of sovereignty.

The 'authority to manage risks' mentioned here is not an abstract concept.

It refers to the authority to participate in the decision-making process on where to set the red lines for nuclear deterrence and where to stop if a conflict escalates.

Furthermore, it includes the authority to codify conditions that block or limit automatic military intervention and to pre-define the scope of trade and industrial burdens linked to the National Defense Strategy.

Without such authority, participation in the theater could place a nation in a position of bearing only the consequences without controlling the risks. This signifies a structure where the risk of war and the costs of peacetime simultaneously increase, but there is no involvement in the decisions regarding nuclear deterrence and escalation management.

Conversely, the choice to maintain an ambiguous neutral ground between the U.S. and China is also unlikely to be a realistic option.

The Korean Peninsula is already included in the Indo-Pacific theater, and in the event of a crisis, it is highly likely to be involved regardless of any declaration of neutrality.

Neutrality is not a strategy to avoid crises, but a path that leads to a loss of options when a crisis strikes.

Ultimately, South Korea's options converge into three paths:

To remain part of the theater and be automatically involved; to remain as a partner that cooperates but postpones decisions; and to step forward as a designer participating in setting theater conditions.

The reason why participation in design is being discussed as a realistic option is simple: South Korea is already within the theater, and risks and responsibilities are unavoidable.

The issue is not whether to participate, but whether South Korea can secure the authority to manage those risks.

The U.S. National Defense Strategy has already set the direction.

The Indo-Pacific is not a space of choice but a designed theater, and allies either participate in its design or become subjects of management.

Wartime operational control, the Indo-Pacific strategy, and nuclear deterrence and trade are no longer separate agendas.

What South Korea needs now is not ambiguous balance, but clear design.

Whether or not to participate in this design will determine the cost structure of South Korea's security and economy going forward.

https://media.defense.gov/2026/Jan/23/2003864773/-1/-1/0/2026-NATIONAL-DEFENSE-STRATEGY.PDF?utm_source=chatgpt.com