[NATO-IP4 Forum] ③ The First Maritime Defense Line and Maritime Transport Routes Revealed by the U.S.-Iran War, and Freedom of Navigation in the Surrounding Regions

YouTube link: https://www.youtube.com/watch?v=S7iEp8mRgco&si=2UUKa4tn-1IWT5ae

Video script

Key Concepts of Maritime Security: Primary Maritime Defense Line and Maritime Shipping Routes

I have prepared the previous slides. I will discuss maritime security. Regarding NATO IP and alliances, Dr. Lee Sung-won can elaborate in detail, so I will focus on my doctoral dissertation topic, which involved historical comparative research on maritime defense lines, applying it to the 21st-century US-China case. While writing my dissertation, I organized the content and recently applied it to the recent wars involving the United States. The core content revolves around the first maritime defense line and maritime shipping routes. While you may have heard a lot about maritime shipping routes, I would like to emphasize the distinct concept of the first maritime defense line.

I would like to clarify that these two concepts are distinct. As I primarily tracked the first maritime defense line in my doctoral dissertation, I felt that it is conceptually different from maritime shipping routes. Particularly during the period of maritime power transition between the US and China, we must understand the phenomenon of the United States, as the maritime hegemon, attempting to adjust the first maritime defense line. For example, Trump's request for China to send ships to the Strait of Hormuz to remove mines or to ask China or allies to take responsibility for the Strait of Hormuz may seem strange. Of course, there are peculiar aspects of Trump, but I want to point out that there are also structural conditions that allow Trump to act in such a manner.

As mentioned, the US wars should be understood as events occurring in a context where the US is focusing on and readjusting the first maritime defense line centered on the Western Hemisphere and the Asia-Pacific amid the ongoing maritime power transition between the US and China. Conceptually, the first maritime defense line and maritime shipping routes are different, and empirically they may or may not align. As Professor Kang Gi has pointed out, we have taken the maritime shipping routes for granted as being open. This was possible before the maritime power transition between the US and China, when the US, as the maritime hegemon, projected naval power globally and maintained a situation where the first maritime defense line and maritime shipping routes were aligned. In the context of the ongoing maritime power transition between the US and China, the US feels the need to readjust this.

Thus, the US is in a situation where it must concentrate on the first maritime defense line in the Western Hemisphere and the Asia-Pacific or Indo-Pacific region. In this context, the Strait of Hormuz or the Gulf region, which could previously be viewed as both a first maritime defense line and a maritime shipping route, has now significantly diminished in importance from a military security perspective. From the perspective of maritime shipping routes, the US's energy dependence on the Gulf region has greatly decreased, leading to a substantial reduction in the value of the Gulf region from the US's standpoint as a maritime shipping route. In this structural context, Trump has been engaging in negotiations to resolve the situation of war and blockade in the Strait of Hormuz, which has repeatedly broken down and escalated into attacks. Behind this lies a situation where the maritime defense line and the first maritime defense line do not align with maritime shipping routes.

Concept and Historical Evolution of the Primary Maritime Defense Line

Although the Strait of Hormuz is not the first maritime defense line, it is a maritime shipping route, and the value of the maritime shipping route itself has significantly diminished. It is essential to understand this situation. Conceptually, the maritime defense line is not a concept I created; it is something Roosevelt discussed. Roosevelt served as the only three-term president in US history from 1934 to 1941. After that, constitutional restrictions were imposed, allowing only two terms, which Trump will also face.

This concept refers to the surrounding areas, meaning that the surrounding areas are the central areas and the mainland. Although geographically distant from the mainland, it is believed that defense must begin from somewhere in the perspective of a maritime hegemon. If, for example, Japan were to enter Portland or Seattle from the Pacific, defense should not start there. According to Roosevelt's thinking, defense should already begin approximately 3,000 to 4,000 miles out. This is our first maritime defense line, which he described as 'a series of islands'; these chain-like archipelagos constitute our first maritime defense line. In the Atlantic, since ground warfare was taking place, 'a series of countries'—that is, several nations—formed our first defense line, but Roosevelt stated that by 1941, the archipelagos in the Atlantic should also be included in the first defense line. This is independent of geographical distance and can vary depending on how a maritime hegemon sets it and how it readjusts during the process of maritime power transition. Particularly when the US maritime power transition occurs, it is a region where the challenger may attempt to expand, reducing the use of military force and the risk of war.

The economic logic and security implications of maritime shipping routes.

On the other hand, maritime shipping routes originate from economic logic. They are places where the flow of trade, energy, food, raw materials, and goods occurs. Trade or resource dependence follows economic logic. If the first maritime defense line is the line that must be protected militarily, maritime shipping routes serve as supply lines during wartime. In peacetime, the maritime routes through which trade, resources, and energy flow can be the most critical shipping routes. While the overwhelming naval power of a maritime hegemon can align and sustain these, when the maritime power transition is shaken, the maritime hegemon may adjust this or seek allies. For instance, the UK may transfer its sphere of influence in the Western Hemisphere to the US or ally with Japan to contain Russia as a friendly force in Asia. In other words, when a maritime power transition does not occur, stable maintenance is possible, but when it does, the first maritime defense line can be adjusted in various ways, handed over to allies, or responsibilities can be delegated to friendly forces. In the case of the current US wars, I interpret it this way: the flow of the US, the Gulf region.

The importance of the Gulf region, which was previously a very significant oil shipping route, has been emphasized since the shale revolution; however, recently, the US's dependence on Gulf oil has dropped from 25% to 8%. The US has transitioned from being a net importer of energy to a net exporter, recording the highest LNG and oil export volumes in history. In other words, the value as a maritime shipping route has significantly diminished. At the same time, the US's surface fleet is deployed worldwide, with the Bahrain Manama base in the Gulf region serving not as a home port for the Fifth Fleet but as a naval support base. This is different from the home port of Japan's Seventh Fleet. In contrast, the Bahrain Fifth Fleet base serves only to support the aircraft carrier strike group coming in and out.

While it cannot be said that this has been excluded from the first maritime defense line, the value as a first maritime defense line has also significantly weakened, which can be seen as something Trump himself has created. I mentioned that in regions where these two concepts align, the maritime hegemon can use military force, and especially when a challenger expands, it may even risk war in that direction. However, I believe the reverse does not hold.

Just because a war occurs does not mean that the region is necessarily a first maritime defense line or a region of great military security importance. Looking at the wars in the Middle East, there have been the War on Terror after 9/11, the Iraq War, and the Afghanistan War. These wars were attempts by the US to shape the Middle Eastern order according to its preferences, but I do not see them as wars conducted for significant strategic gains. Wars can be conducted for various reasons, and particularly, just because a war with low risks is conducted does not mean that only wars with low risks will be conducted afterward. The reasons for various wars can lead to the outbreak of conflict, so the reverse does not hold.

Therefore, just because a war is currently being waged does not mean that this area is important. Rather, it is because it is not an important area that airstrikes are being conducted, and all personnel and families stationed at the naval logistics base of the Fifth Fleet have been withdrawn. In fact, there may be no personnel left, with only base support remaining. Instead, the aircraft carrier strike group comes in and out to provide support. The importance has rather diminished, and the significance of the Strait of Hormuz and the Gulf region in the first maritime defense line has relatively decreased, and the value as a maritime shipping route has also diminished, which I believe is evidenced by this situation.

The language strategy of the maritime hegemon: Mare Liberum and Mare Clausum.

These two concepts are somewhat different. The first maritime defense line has a more closed feeling, characterized by an attempt to prevent penetration by other challenger states and emphasizes maritime sovereignty. In contrast, maritime shipping routes use open language advocating for 'freedom of navigation.' Maritime hegemons have used both of these depending on the situation. Tracing the origins of the concepts 'Mare Liberum' and 'Mare Clausum,' the language was first used by the UK against Spain to refute Spain's monopolistic maritime possession.

Subsequently, the Netherlands also used it when asserting maritime claims from the UK mainland. It began with the question of whether the Dutch East India Company had the international legal right to seize the Portuguese merchant ship Santa Catarina and harvest the spoils within. Grotius, employed by the East India Company, argued that since it was acquired in the high seas where everyone has rights, they had the right to obtain the spoils. This is Grotius's theory of free seas, 'Mare Liberum'.

In response, the UK initially spoke of 'Mare Liberum,' but as the naval power of the Netherlands rose, it began to use different language in the mid-17th century. The UK asserted maritime sovereignty around the British Isles, using closed language again, and this was Sheldon’s 'Mare Clausum,' which debated Grotius. In other words, maritime hegemons use this first maritime defense line language in their first maritime defense line, while when going offshore to protect maritime shipping routes and simultaneously defend the first maritime defense line, they may speak of 'freedom of navigation.' This persists and is sustained when the maritime hegemon possesses overwhelming naval power.

Analysis of the discrepancies between the first maritime defense line and maritime shipping routes.

There are three cases: Venezuela and the 18th-century crisis in Guayaquil, and Roosevelt's concept of island defense lines. What I want to show through these three cases is that there are times when the concepts of the first maritime defense line and maritime shipping routes align and times when they do not. In the case of the current US wars, I see it as a state of misalignment, where the Strait of Hormuz or the Gulf region is effectively excluded from the first maritime defense line. However, I believe there is still some value as a maritime shipping route. Therefore, the US tells its allies to handle it themselves or to carry out mine removal operations. It even asks China to come and take care of it.

A similar case is Venezuela. There was a territorial dispute between the US and the UK over Venezuela in 1895. At that time, the President of Venezuela requested intervention from the US to expel the UK. The US showed a willingness to go to war and negotiated with the UK, leading to a crisis.

During this period, the UK was readjusting its maritime defense line centered on the mainland, India, and Suez, as maritime challengers such as the US, Germany, and Japan were simultaneously rising. The UK transferred its sphere of influence in the Western Hemisphere to the US and withdrew. In Asia, it transferred some of its sphere of influence to Japan through the Anglo-Japanese Alliance, and in the Mediterranean, it maintained the balance of power by bringing France into the alliance through negotiations with France and Britain. At the same time, the UK responded by focusing on the defense of the German mainland and strengthening the defense of its main base. I believe this is similar to the current situation in the Strait of Hormuz. In another case, when the naval capabilities of the maritime hegemon are maintained and a state of alignment is sustained, the maritime hegemon shows a willingness to go to war.

Just now, that is.

During this period, the UK was readjusting its maritime defense line centered on the mainland, India, and Suez, as maritime challengers such as the US, Germany, and Japan were simultaneously rising. The UK transferred its maritime sphere of influence in the Western Hemisphere to the US and withdrew. In Asia, it transferred some of its sphere of influence to Japan through the Anglo-Japanese Alliance, and in the Mediterranean, it maintained the balance of power by bringing France back into the alliance through negotiations with France and Britain.

At the same time, the UK responded by focusing on the defense of the German mainland and strengthening the defense of its main base. I believe this is similar to the current situation the US is showing in the Strait of Hormuz. When the naval capabilities of the maritime hegemon are still maintained and a state of alignment can be sustained, the maritime hegemon shows a willingness to go to war against challengers, especially regarding the second maritime defense line.

In the case of a second-tier challenger, Britain even adjusted its first maritime defense line towards Alexandria, which was originally Constantinople. The British maritime defense line in the Mediterranean was focused on Constantinople to contain Russia, but during this period, Russia and France formed an alliance. By 1894, if we look at the naval balance in the Mediterranean, combining Russia and France puts them in a situation almost equal to Britain. Therefore, from Britain's perspective, while France alone had a navy that was necessarily inferior to Britain's,

When France attempted to invest power in the direction of Suez, particularly in the direction of Fashoda, which is the upper Nile region, this overlapped with its first maritime defense line, Alexandria, and the major maritime shipping route, Suez. Therefore, it attempted to repel France even by using military force. In a way, there was no need to repel France because the UK was already at a disadvantage in naval power. However, at the point where the first maritime defense line and maritime shipping routes overlap, the UK mobilized its naval power to repel France. Since France had no intention of going to war, it naturally withdrew. And now, we turn to Roosevelt's discussion.

The US's conception of maritime order and the first maritime defense line.

Roosevelt's conception of the first maritime defense line did not originate during the Pearl Harbor period in the Pacific. In 1934, he already directed studies on military bases in the Philippines, Midway, and the Aleutians, expressing a desire for as many bases as possible. He had mentioned that it would be good to have air force or naval bases and asked whether it would be possible to create such bases shortly after taking office in 1934. By 1936, he stated that Hawaii had become the center of our maritime defense line, and in 1937, he envisioned a scenario in which, when a challenger state attempted to destroy asymmetric shipping routes, and Japan expanded its maritime shipping routes, how to block it through base lines in Hawaii, the Philippines, Java, and Singapore. Thus, such a conception was already present.

When Japan's expansion concentrated in Southeast Asia, the US's motivation for war was activated. This was also the first maritime defense line that FDR envisioned, and this region, which is now referred to as the island defense line, was simultaneously a major maritime shipping route, indicating that the US already had a strong willingness to use military force. Therefore, in 1939, the concept of US maritime hegemony and maritime route protection was actually initiated by the US Foreign Relations Council in 1940. The Second World War had already begun, and through five research topics—economic and financial, security, territorial expansion, peace purposes, and politics—there was a discussion on how to conceive the post-war order. Remarkably, within a month in 1940, there was a conception of this sphere of influence that changed drastically. Initially, it started in the Western Hemisphere. However, after that, it began with this extent, excluding Greenland.

It started from this extent, excluding Greenland, and then a month later included Greenland and Latin America. Then it included all of Asia and the Pacific. By September and October, it aimed to secure maritime routes in all regions except for the areas occupied by the Soviet Union and Nazi Germany, projecting military bases to respond to any forces attempting to disrupt the economic system and global capitalism during the Great Depression. This international order was conceived at that time, and remarkably, it was implemented by the US in 1942 and beyond.

Structural changes in modern maritime security and Korea's challenges.

The US Foreign Relations Council referred to this as 'the Great Area,' which was firmly established through the Cold War and post-Cold War periods, forming the maritime order we are familiar with. Therefore, the conclusion is that the maritime shipping routes and the first maritime defense line do not align, which allows us to understand the US's wars and why they are trying to shift the role of maritime route protection to other areas. This part summarizes the fleet redeployment.

Thus, calling China to the Gulf region, which can be called upon, is absurd. I believe this would not be possible if it were the first maritime defense line. Moreover, from the perspective of energy security, dependence on the Gulf region has already decreased significantly, and the US has become a net exporter of energy. Additionally, from Trump's personal worldview, there was animosity towards Iran, and he believed that military intervention should secure resources or financial gains rather than necessarily achieving strategic interests. Therefore, one might think that since we do not depend on energy, there is no need to be cautious here.

Europe has already been conducting operations in the Red Sea with a multilateral initiative. This was an operation conducted by the EU, known as Operation Aspide, which included the Strait of Hormuz in its operational scope. Therefore, France sent one or two more ships, stating that they would do more, and this was promoted at the EU level and NATO level, but it was not properly followed up. In the case of IP4, it is somewhat distant and does not have a direct impact, but while the energy security situation is directly affected, it has not been directly impacted from a military security perspective, so there has been a response of various joint statements.

Finally, I would like to mention that the US is currently discussing the first maritime defense line, which initially included Japan, the Ryukyu Islands, Taiwan, the Philippines, and Australia. However, during a recent speech by Dr. Lee Seong-hwan at the Sejong Institute, Korea was included for the first time. Upon closer examination, it seems that Korea was included not so much as part of the first maritime defense line but rather for the purpose of integrating deterrence posture. However, according to the interpretation of this speech by the Voice of America, the first maritime defense line is still defined as Japan, the Ryukyu Islands, Taiwan, and the Philippines.

Therefore, how we interpret this part seems to be important. Lastly, I would like to mention that when we have similar mutual engagements in the Taiwan Strait and the South China Sea, this is an area of alignment. That is, in this area, which is both a maritime shipping route and simultaneously a first maritime defense line, especially a maritime blockade by China could occur. We need to consider how we should respond in such a scenario, what we should do in terms of the ROK-US alliance, or whether there are proactive plans we should prepare at the NATO IP4 level, particularly regarding the maritime blockade scenario. I do not think an invasion of Taiwan will occur immediately, but the maritime blockade scenario is very possible, and in that case, we need to discuss how we should respond and what the US's likelihood of using military force is, and we need further discussions on this matter as I conclude my presentation. Thank you.