North Korea and the World: The Interconnection of the Korean Peninsula and the Taiwan Strait and the US ‘Alliance Transformation’

YouTube Link: https://www.youtube.com/watch?v=Feei02uW5H8

Video Script

When a crisis occurs in the Taiwan Strait, South Korea might say, 'We will not continue our relationship.' The moment South Korea draws a line, saying, 'This is not our business,' I believe the (mutual defense treaty) will become a mere formality. Hello, and thank you for watching EAI's North Korea and the World. Today, we must discuss the issue of the United States, continuing from last time. It's not simply an issue of the United States, but ultimately an issue of alliances. In particular, there have been many important statements from the Trump administration recently. One of the reasons I continue to bring this up is that the Trump administration's defense grand strategy has not yet been precisely determined, leading to much speculation and conjecture. At such times, it is crucial for South Korea to carefully review this and develop its own strategy, especially with the presidential election not far off, it is very important for the new government to prepare such a strategy. Therefore, as a researcher, I will continue to discuss this issue.

The Meaning of Commander Brunson's Remarks and the Transformation of Indo-Pacific Alliances

Please understand that I must continue to discuss this. Today, I intend to discuss the U.S. Army's Pacific Landpower Symposium and Defense Exhibition, known in English as RIMPAC, which took place on May 15th. At RIMPAC, General JB "Xavier" Brunson, Commander of U.S. Forces Korea and Combined Forces Command, who is also the senior U.S. Army officer in Korea and a key figure, made a statement. This was reported by domestic media to a considerable extent, and it was a remark of significant meaning. Today, focusing on those remarks, we will discuss the Trump administration, which we have been discussing continuously, and it does not seem to be solely an issue of the Trump administration.

The United States is attempting to transform its alliances not only in the Indo-Pacific region but globally. In the context of this alliance transformation, the ROK-U.S. alliance and the role of U.S. Forces Korea are naturally being re-examined, and the issues of the Taiwan Strait and the Korean Peninsula, which are discussed as the most serious and likely military conflicts in the Indo-Pacific region, are all being discussed in relation to each other. Therefore, today, we will organize these points, focusing on Commander Brunson's remarks. The RIMPAC U.S. Army Pacific Landpower Symposium, as mentioned earlier, is held annually. The core objective of this symposium is that it is organized by the U.S. Army.

The Strategic Location of the Korean Peninsula and the 'Tyranny of Distance'

Therefore, it has the character of emphasizing the role and importance of the U.S. Army's ground forces. Thus, we need to listen with this in mind. I will discuss this further later. The discussion topics at this year's event, held in Honolulu, Hawaii, for 2025, primarily focused on the contribution of U.S. ground forces and the U.S. Army in the Indo-Pacific region, specifically how the U.S. Army can contribute to regional security and combined operations. Of course, there were also topics such as strengthening alliances and partnerships. These are Commander Brunson's remarks. First, he discusses the strategic location of the Korean Peninsula. Several key concepts emerge, one of which is the expression 'tyranny of distance.'

This is expressed in English as 'tyranny of distance.' What does this mean? The United States is very far from the Korean Peninsula and the Indo-Pacific. However, it maintains forces forward-deployed in the region, including U.S. Forces Korea and U.S. Forces Japan. Naturally, there is the threat from North Korea, and in a broader context, the intention is to prepare for the threat from China. If ground operations were to occur in this region, whether in the Taiwan Strait or on the Korean Peninsula, it would be difficult for the United States to move quickly due to its vast distance.

On the other hand, China, being in the region, can respond much faster and more rapidly. In this sense, 'tyranny of distance,' how to reduce this vast distance, is important from the perspective of U.S. strategists. Commander Brunson states that the strategic location of the Korean Peninsula is very important in this regard. There is a quote, which I will read verbatim. What immediately struck me as I looked at the map was the location of the Korean Peninsula. It is part of the Asian continent, with a significant U.S. military presence, and when viewed from space at night, South Korea appears like a fixed aircraft carrier floating in the sea between the island of Japan and mainland China. The expression 'fixed aircraft carrier' is used in English. Domestic media have widely reported this statement, comparing the Korean Peninsula itself to an unsinkable aircraft carrier. This is often mentioned in comparison to Admiral Harry Harris's remarks about Japan, but...

The important point is that, from Commander Brunson's perspective, the strategic location of the Korean Peninsula is highly significant, and it metaphorically signifies a strategic position from which power can be projected, much like an aircraft carrier. This is the first key point, I believe. To summarize again, this statement emphasizes that South Korea's strategic location is crucial for the United States to respond quickly to conflicts in the Indo-Pacific region. The second point directly addresses the containment of China.

The First Island Chain and South Korea's Importance for Containing China

It emphasizes South Korea's strategic importance for containing China. It states that South Korea is located within the First Island Chain and is the closest ally to Beijing. The terms 'First Island Chain,' 'Second Island Chain,' and 'Third Island Chain' are mentioned. Let me briefly explain the island chains again. It is called the 'first island chain' in English, and it is a hypothetical maritime defense line that emerged from a strategic concept by the United States and its allies to deter and contain China's maritime expansion. The First Island Chain includes mainland Japan, Okinawa, Taiwan, the Philippines, and northern Borneo.

Overall, it spans the East China Sea, the Taiwan Strait, and the South China Sea, encompassing maritime nations and islands within approximately 1,500 km of China's coast. Naturally, the Korean Peninsula, South Korea, is also included here. Therefore, Commander Brunson emphasized that South Korea is located on the front line, crucial for preventing China's southward advance, and is particularly closest to Beijing in terms of distance. Camp Humphreys, the largest U.S. Army ground base in Pyeongtaek, is only 840 km from Beijing in a straight line.

The Mutual Defense Treaty and the Potential Linkage to the Taiwan Strait Crisis

This confirms that it is very close. Commander Brunson then makes another statement. He says that South Korea has played a very important role in U.S. security strategy since the Cold War, and today it is closely linked to China's maritime expansion and the issue of the Taiwan Strait. Ultimately, the role of U.S. Forces Korea is inevitably linked to the issues within the Taiwan Strait region, and beyond the role of U.S. Forces Korea, South Korea's position as an ally is also relevant. This is clearly confirmed once again. He also makes another significant statement. He says that South Korea has a mutual defense treaty with the United States.

He states that the Korean Peninsula is located at the center of the Asian map, and that South Korea, Japan, and the Philippines are connected to the United States through mutual defense treaties, forming a triangular axis of these three countries. Considering the map, the triangular axis connecting South Korea, Japan, and the Philippines is essentially a triangular axis for containing China, and the characteristic of these three countries is that they have mutual defense treaties. A mutual defense treaty, as the name suggests, is about reciprocity. It is not about protecting and defending only one party, but about treaty obligations between them. For example, Article 2 of the Mutual Defense Treaty between the ROK and the U.S. states: 'Whenever either Party recognizes that the political independence or security of either of the Parties is threatened by external armed attack, the Parties shall, after consultation, take action in accordance with their constitutional processes.' It further states: 'To this end, each Party will continue to strengthen its independent and collective capacity to resist armed attack, and will consult and cooperate in the implementation of this Treaty.' In other words, for example, a slight...

Let me present a scenario. If a full-scale military conflict between China and Taiwan begins in the Taiwan Strait, and the United States intervenes, this would constitute a situation where the United States' security is threatened by external armed attack. In that case, according to the mutual defense treaty, South Korea also has an obligation to consult and cooperate with the United States on this matter. I do not believe there is much room for alternative interpretations. This is because the treaty mentions consultation and cooperation. If a crisis occurs in the Taiwan Strait, South Korea could, in an extreme situation, say it will not participate. However, the mutual defense treaty implies joint response through consultation and cooperation. Therefore, if South Korea were to draw a line, saying 'this is not our business,' without consultation and agreement, I believe the mutual defense treaty would effectively become a mere formality. I do not think this reinterpretation is significantly flawed. This is based on the treaty provisions, but then...

The Possibility of the Korean Peninsula Becoming a Battlefield During a Taiwan Strait Crisis

Let me explain this in practical terms. What I have consistently emphasized is the interconnectedness of the Taiwan Strait issue and the Korean Peninsula. From this perspective, if China invades Taiwan, the Korean Peninsula could immediately become a battlefield. This is because if China invades Taiwan and the United States begins to intervene militarily, a situation will arise where China's North Sea Fleet and East Sea Fleet move down towards Taiwan. Our West Sea lies along this route. If the U.S. decides to intervene militarily, it cannot allow this Chinese fleet moving down the West Sea to proceed unimpeded. The U.S. Air Force in Korea is highly likely to attempt to block this route, potentially utilizing the Osan Air Base. Conversely, China is well aware of this and may consider preemptive strikes against U.S. military bases in Korea. These are not my own speculations; such scenarios are already being discussed extensively in U.S. think tanks.

Therefore, this directly links the Taiwan Strait conflict to the situation on the Korean Peninsula. The U.S. military bases in Korea are, as you know, located within South Korea. An attack on these bases would directly involve us, making it impossible to remain uninvolved. There are many discussions on this, and while I don't fully agree with all of them, a prominent example is the scenario outlined by the Center for Strategic and International Studies (CSIS) in 2024, which suggests that a crisis in the Taiwan Strait would simultaneously increase the risk of a crisis on the Korean Peninsula. This implies the possibility of North Korea launching a diversionary attack against South Korea. The idea is that if there is a military conflict in the Taiwan Strait, China might collaborate with North Korea to launch limited military provocations against South Korea, thereby tying down U.S. forces in the region. This is to say that China would manipulate North Korea to keep U.S. forces occupied.

I personally do not see this as highly probable, given the current state of North Korea-China relations and the significant risks North Korea would undertake. However, I cannot completely dismiss this possibility because the future is uncertain. While North Korea is currently distancing itself from China and cooperating with Russia, its ultimate vision of a new Cold War framework involves alignment with China and Russia. Therefore, North Korea might view the Taiwan Strait issue as its own concern. Furthermore, there is a mutual defense treaty between North Korea and China, the Sino-North Korean Mutual Aid and Cooperation Treaty, which could be invoked. For these reasons, I believe this possibility cannot be entirely ruled out. Another factor is that approximately 30% of South Korea's maritime transport passes through or near the Taiwan Strait. Thus, if a military conflict occurs there,

The Impact of a Taiwan Strait Crisis on the South Korean Economy

it would inevitably deal a direct blow to the South Korean economy, necessitating our involvement in some form. Last year, Bloomberg Economics published an analysis estimating the economic effects of a Chinese invasion of Taiwan. While focusing on indirect effects, their projections indicated that Taiwan would be most severely impacted, followed by South Korea. For instance, it was estimated that Taiwan's Gross Domestic Product (GDP) would decrease by 40% in the first year of the war, while South Korea's GDP would decline by 23.3%. These figures highlight the severity of the potential economic repercussions.

Expanded Role of U.S. Forces in Korea: Responding to China and Russia Beyond North Korea

Therefore, from economic and security perspectives, the Taiwan Strait issue is undeniably linked to the Korean Peninsula. Returning to General Brunson's remarks, the third point he emphasized was the role of U.S. Forces Korea (USFK). He explicitly stated that the existing role of USFK, which has traditionally focused on deterring North Korea, must now encompass responses to both China and Russia. To ensure accuracy, I will quote General Brunson's statement directly: "The role of U.S. Forces Korea is not solely focused on repelling North Korea. As a small part of a larger Indo-Pacific strategy, it also focuses on operational activities and investments in the region." He further elaborated that the presence of U.S. ground forces provides deterrence against North Korea, Russia, and China, while offering various options to U.S. policymakers. This clearly indicates an expansion of USFK's mission from solely countering the North Korean threat to also addressing threats from China and Russia.

This statement from the Commander of U.S. Forces Korea carries significant weight. Prior to General Brunson, General LaCamera explicitly stated on multiple occasions that the primary role of USFK was to prepare for the North Korean threat and not for China or Russia, drawing a clear line. I believe this is the first time a Commander of U.S. Forces Korea has explicitly mentioned China and Russia in the context of expanding USFK's role. This is significant because, as I explained in previous videos, the Trump administration's national defense strategy, outlined in the interim National Security Strategic Guidance released in late March, identifies China as the primary threat and the central focus of U.S. strategy, even using the word 'only' to emphasize this point. Consequently, the primary role of forward-deployed U.S. forces in the Indo-Pacific region, including USFK and U.S. Forces Japan, must inevitably shift towards countering China.

U.S. Strategy to Counter China and the Role of U.S. Forces Korea

General Brunson's remarks align perfectly with this strategic shift. From the perspective of the regional commander responsible for USFK, expanding the primary mission to include China and Russia is not a trivial matter. I believe General Brunson is fully attuned to the prevailing sentiment in Washington. Emphasizing the importance of ground forces carries a specific implication: there is a movement within the U.S., as exemplified by Elbridge Colby's arguments, to reduce the emphasis on ground forces and restructure towards air and naval power.

The emphasis on the role of ground forces, particularly from the perspective of the regional commander, suggests a strategic recalibration. General Brunson's statement that the primary mission extends beyond North Korea to include China and Russia is significant. This indicates an awareness of the evolving geopolitical landscape and the need for USFK to adapt its posture accordingly. The U.S. strategy, as highlighted in documents like the interim National Security Strategic Guidance, increasingly views China as the primary threat, necessitating a strategic focus on countering its influence in the Indo-Pacific. Therefore, the role of U.S. forces stationed in the region, including those in Korea and Japan, is naturally aligning with this objective.

Emphasis on Ground Force Roles and Discussions on USFK Troop Levels

Given that this conference is hosted by the U.S. Army, it is natural for General Brunson to emphasize the importance of ground forces. This reinforces the speculation that discussions are already underway in Washington regarding a potential reduction in the size or role of U.S. ground forces in Korea, and that these discussions have likely been communicated to the Commander of U.S. Forces Korea. Therefore, his emphasis on the importance of ground forces, considering responses not only to North Korea but also to China and Russia, appears to be a strategic communication.

Interconnectedness of the Korean Peninsula and Taiwan Issues, and Implications for Alliance Transformation

This interpretation is certainly plausible. If so, it signifies a substantial shift in the traditional role of the ROK-U.S. alliance and U.S. Forces Korea. Despite being in a position to protect his core mission and interests, the Commander of U.S. Forces Korea appears to be in a situation where he must agree to an expanded role. In conclusion, two clear directional trends are confirmed.

First, the issues of the Korean Peninsula and Taiwan are now inextricably linked. This must be understood as a clear reality, especially in light of attempts to undermine existing alliance treaties and, by extension, the ROK-U.S. alliance. Second, there is an alliance transformation. The evolving role of U.S. Forces Korea ultimately signifies a change in the role played by U.S. forces within the ROK-U.S. alliance. This can manifest in two ways. One is the expansion of USFK's role, as desired by General Brunson, arguing that the importance of U.S. ground forces stationed in Korea must be strengthened to address threats not only from North Korea but also from China and Russia. The other is the opposite direction, driven by pressure from Washington.

The South Korean Government's Choices and the Future of the ROK-U.S. Alliance

There is also a clear movement to reduce the role of U.S. Forces Korea and restructure towards air and naval forces to counter the threat from China. The most crucial factor here is the decision of the South Korean government. It is imperative to understand this situation and decide whether to join the U.S. in this alliance transformation, refrain from participating, or adopt a middle ground that considers both perspectives. This decision will fundamentally shape the ROK-U.S. alliance, the nature of U.S. Forces Korea, and the extent to which South Korea participates in the U.S.'s alliance transformation. I believe this decision rests not solely on U.S. pressure but on the choices made by our government. I will conclude here for today.

Thank you.

■ Park Won-gon, Director of the North Korea Research Center at the East Asia Institute (EAI) and Professor of North Korean Studies at Ewha Womans University.

■ Managed and Edited by: Park Han-soo, EAI Research Fellow

Inquiries: 02 2277 1683 (ext. 204) | hspark@eai.or.kr