[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

Structural Changes in Maritime Security and the First Maritime Defense Line

Based on the content prepared in the previous slide, I will now discuss maritime security. Dr. Lee Seong-won will elaborate on NATO IP and alliances, so I intend to apply the historical comparative research on maritime defense lines, which was the subject of my doctoral dissertation, to the 21st-century US-China case. I have briefly organized the content I compiled while writing my dissertation in relation to the recent US-Iran conflict. The core concepts are the first maritime defense line and sea lines of communication (SLOCs). While you are likely familiar with SLOCs, I aim to differentiate them from the concept of the first maritime defense line.

I want to emphasize that these two concepts are distinct. In my doctoral dissertation, I primarily traced the first maritime defense line and strongly felt it was a different concept from SLOCs. Specifically, understanding the US-Iran conflict is crucial when considering the maritime power transition between the US and China. Trump's remarks regarding the Strait of Hormuz, such as ordering China to send ships to clear mines or asking China and its allies to take responsibility for the Strait of Hormuz, might seem peculiar. While Trump has his eccentricities, there are structural conditions that enable him to act in such ways, which I will explain.

The US-Iran conflict should be understood as an event occurring within the context of the US-China maritime power transition, where the US is focusing on and readjusting its first maritime defense line, primarily centered on the Western Hemisphere and the Asia-Pacific. Conceptually, the first maritime defense line and SLOCs are different, and experientially, they may or may not coincide. As Professor Kang Ki mentioned, we have naturally assumed that SLOCs are open. This was possible because, prior to the US-China maritime power transition, the US could project naval power globally, maintain naval bases, and thus ensure the alignment of the first maritime defense line and SLOCs. However, in the current situation of US-China maritime power transition, the US feels the necessity to readjust this alignment.

Therefore, the US must concentrate on its first maritime defense line in the Western Hemisphere, Asia-Pacific, or Indo-Pacific region. In the past, the Strait of Hormuz and the Persian Gulf region could have been considered both a first maritime defense line and a sea line of communication. However, from a military security perspective, their importance has significantly diminished or they have been excluded from the first maritime defense line. Furthermore, as US dependence on energy from the Persian Gulf has substantially decreased, their value as SLOCs has also diminished. Within these structural conditions, Trump is repeatedly engaging in conflict and blockade situations in the Strait of Hormuz, negotiating with allies to lift the blockade, only for it to break down again and lead to attacks. Behind this lies the mismatch between the first maritime defense line and SLOCs.

Concept and History of the First Maritime Defense Line

The situation is that the Strait of Hormuz is a sea line of communication, though not part of the first maritime defense line, and the value of the sea line of communication itself has also significantly decreased. This is the context that needs to be understood. To elaborate on the concept, the idea of a maritime defense line is not one I originated; it was articulated by Roosevelt during his unprecedented nearly three terms as president from 1934 to 1941. The constitutional amendment later limited this to two terms. Trump will likely be the last.

This concept implies that defense must begin from the perspective of a maritime hegemon in the surrounding areas, that is, geographically distant locations excluding the homeland. Instead of allowing the threat to reach the homeland, for instance, if Japan were to advance to Portland or Seattle from the Pacific, Roosevelt's idea was to initiate defense from 3,000 to 4,000 miles away, rather than from the point of entry. That is our first maritime defense line, and he described 'a series of islands' as our first maritime defense line. In the Atlantic, because ground battles were occurring, 'a series of countries' constituted our first defense line. Although Poland and others fell, ultimately, these various countries were our first defense line, and in 1941, Roosevelt stated that island chains in the Atlantic should also be included in the first defense line.

This is independent of geographical distance and can change depending on how a maritime hegemon establishes it and how it is readjusted during the process of maritime power transition. Particularly when a challenger nation has a strong expectation of expanding in this direction during a maritime power transition, this can be an area where the use of military force and the risk of war can be reduced.

Distinction between Maritime Lines of Communication and the First Maritime Defense Line

On the other hand, maritime lines of communication originate from economic logic. They involve the flow of trade, energy, food, raw materials, and goods. This is based on economic logic, which is more closely related to trade and resource dependency. If the first maritime defense line is a line that must be secured for military security, then maritime lines of communication become supply routes during wartime. In peacetime, maritime routes through which trade, resources, and energy flow can become the most crucial lines of communication. While a maritime hegemon's overwhelming naval power can align and sustain these, when maritime power transitions cause instability, the hegemon may adjust them or seek alliances. For instance, Britain ceded its sphere of influence in the Western Hemisphere to the United States and allied with Japan to counter Russia in Asia. In other words, stable maintenance is possible when maritime power transitions are not occurring, but when they do, the first maritime defense line can be adjusted in various ways, transferred to allies, or responsibility can be delegated to friendly powers.

I interpret the current US-Iran conflict in the following way. While the Gulf region was a crucial oil transportation route in the past, its importance, emphasized after WWII, has diminished. Recently, the US's oil dependency on the Gulf region has fallen from 25% to 8%. The US has transitioned from being a net oil importer to a net exporter, showing record-high LNG and crude oil export volumes. Consequently, its value as a maritime transport route has significantly decreased. Concurrently, the US Navy's fleet is deployed worldwide, but the US Naval Support Activity Bahrain in the Gulf region is a naval support base, not the homeport for the Fifth Fleet, unlike the Seventh Fleet's homeport in Japan. The Fifth Fleet's base in Bahrain, as a support facility, merely facilitates the arrival and departure of carrier strike groups. While it cannot be entirely excluded from the primary maritime defense line, its value in that capacity has considerably weakened, a situation that could be attributed to Trump himself.

While the Gulf region was a crucial oil transportation route in the past, its importance, emphasized after WWII, has diminished. Recently, the US's oil dependency on the Gulf region has fallen from 25% to 8%. The US has transitioned from being a net oil importer to a net exporter, showing record-high LNG and crude oil export volumes. Consequently, its value as a maritime transport route has significantly decreased. Concurrently, the US Navy's fleet is deployed worldwide, but the US Naval Support Activity Bahrain in the Gulf region is a naval support base, not the homeport for the Fifth Fleet, unlike the Seventh Fleet's homeport in Japan. The Fifth Fleet's base in Bahrain, as a support facility, merely facilitates the arrival and departure of carrier strike groups. While it cannot be entirely excluded from the primary maritime defense line, its value in that capacity has considerably weakened, a situation that could be attributed to Trump himself.

In areas where these two concepts coincide, a maritime hegemon can use military force, especially when a challenger is expanding, and can even accept war in those regions. However, I believe the reverse is not true. The occurrence of war does not necessarily mean that the region is a first maritime defense line or a militarily and strategically crucial area. Wars in the Middle East, such as the War on Terror after 9/11, the Iraq War, and the Afghanistan War, were attempts by the US to shape the regional order in a way it preferred, but they are difficult to view as wars waged for significant strategic gain. Wars can be fought for various reasons, and particularly, conducting low-risk wars does not guarantee that subsequent wars will also be low-risk.

The occurrence of a war in a region does not necessarily mean it constitutes a primary maritime defense line or a strategically vital area. Examining wars in the Middle East, we have seen the War on Terror post-9/11, the Iraq War, and the war in Afghanistan. These conflicts were attempts to shape the Middle East order in favor of US preferences, but they are difficult to characterize as wars waged for significant strategic gain. Wars can be initiated for various reasons, and the fact that a low-risk war is waged does not preclude subsequent wars from also being low-risk.

Therefore, the outbreak of war does not definitively establish a region as important. Rather, the fact that airstrikes were conducted and personnel and their families were evacuated from the Fifth Fleet's naval logistics base in the Gulf suggests its diminished importance. While the base may remain, it might be devoid of personnel. The increased reliance on carrier strike groups for support, with their frequent deployments and withdrawals, further indicates a reduced significance. Consequently, the importance of the Strait of Hormuz and the Persian Gulf as a first maritime defense line has relatively decreased, and its value as a maritime line of communication has also diminished. This event, therefore, serves as a demonstration of these shifts.

Mare Liberum and Mare Clausum

These two concepts differ slightly. The first maritime defense line has a more exclusive nature, aiming to prevent incursions by other challengers and employing language that emphasizes maritime sovereignty. In contrast, maritime lines of communication use open language advocating for 'freedom of navigation.' Maritime hegemons have utilized both concepts depending on the circumstances. Tracing the origins of 'Mare Liberum' and 'Mare Clausum,' the language 'Mare Liberum' was first used by Britain to counter Spain's claims. It was a rebuttal to Spain's exclusive maritime claims.

Subsequently, the Netherlands also adopted this language to contest British claims over its home waters. Initially, the issue began with the Dutch East India Company acquiring the Portuguese merchant ship Santa Catarina and the question of whether it had the international legal right to its captured booty. Hugo Grotius, employed by the East India Company, argued that it did, asserting that since the acquisition occurred on the high seas, where all have rights, the company had the right to the spoils. This became Grotius's doctrine of the freedom of the seas, or 'Mare Liberum'.

In response, Britain, which had initially supported 'Mare Liberum,' began using different language in the mid-17th century as the Dutch navy rose in power. It reasserted claims of maritime sovereignty around the British Isles, employing exclusive language, and John Selden, who debated Grotius, introduced 'Mare Clausum.' This illustrates a situation where maritime hegemons use the term 'first maritime defense line' for their primary defense perimeters, and when defending maritime lines of communication and first maritime defense lines in distant waters close to their shores, they use language such as 'freedom of navigation.' This alignment is sustained and supplied when the maritime hegemon possesses overwhelming naval power.

Cases of Divergence between the First Maritime Defense Line and Maritime Lines of Communication

There are three cases: Venezuela, the 18th-century Fashoda Crisis, and Roosevelt's concept of island defense lines. Through these three cases, I aim to illustrate that there are times when the concepts of the first maritime defense line and maritime lines of communication align and times when they diverge. I believe the current US-Iran conflict represents a divergence. The Strait of Hormuz and the Persian Gulf region have been effectively excluded from the first maritime defense line, although they retain some value as maritime lines of communication. Consequently, the US is asking allies to manage these areas themselves or to conduct mine clearance operations, even urging China to address the issue.

A similar case is Venezuela. There was a territorial dispute between the United States and Britain over Venezuela in 1895. At that time, the Venezuelan president requested US intervention, inviting the US to expel the British. The US adopted a stance of being prepared for war, negotiated with Britain, and a crisis ensued.

Britain, facing the simultaneous rise of maritime challengers such as the United States, Germany, and Japan, was readjusting its maritime defense lines centered around its homeland, India, and Suez. It ceded the Western Hemisphere's maritime sphere of influence to the United States and withdrew. In Asia, it ceded some sphere of influence to Japan through the Anglo-Japanese Alliance, and in the Mediterranean, it brought France into the Entente Cordiale to maintain a balance of power. Simultaneously, Britain focused on defending its homeland, Germany, and strengthening its core defenses. This response is similar to the Strait of Hormuz case observed in the current US-Iran conflict. In other cases, when the maritime hegemon's naval capabilities are maintained and can sustain alignment, the hegemon demonstrates a willingness to go to war, particularly against challengers.

Concurrently, Britain responded by strengthening its homeland defense, focusing its efforts on the defense of its mainland while reinforcing its core territory. I believe this is analogous to the current situation the United States faces in the Strait of Hormuz. In other historical instances, when a maritime hegemon's naval capabilities remain robust enough to maintain a unified defense line, it demonstrates a willingness to engage in conflict. Specifically, in confronting challengers, such a power concentrates its efforts on the primary defense line rather than a secondary one.

Against the challenger with the second-largest naval power, the first maritime defense line was even adjusted towards Alexandria, whereas it was originally Constantinople. Britain's maritime defense line in the Mediterranean was focused on Constantinople to counter Russia, but during this period, Russia and France formed an alliance. In 1894, combining the naval forces of Russia and France created a situation nearly equivalent to Britain's in the Mediterranean. Therefore, from Britain's perspective, while France alone possessed a weaker naval force than Britain,

when France began investing its influence towards Suez, particularly in the Fashoda region, which overlapped with Britain's first maritime defense line at Alexandria and the crucial maritime line of communication, Suez, Britain sought to repel France even by using military force. In a way, there was no need to repel France, as France possessed a weaker naval force and that situation was ongoing. However, at this point where the first maritime defense line and the main maritime line of communication overlapped, Britain mobilized its naval forces to repel France. Since France had no intention of going to war, it naturally withdrew. And now, regarding Roosevelt's narrative.

Roosevelt's conception of the first maritime defense line was not related to the Pearl Harbor period in the Pacific. As early as 1934, he ordered studies on military bases in the Philippines, Midway, and the Aleutian Islands, expressing a desire for such bases if possible. He had discussed the possibility of establishing air or naval bases shortly after taking office in 1934. In 1936, he stated that Hawaii had become the center of our maritime defense line. In 1937, he outlined a plan to block potential challengers attempting to destroy asymmetric sea lanes, such as Japan's expansion of maritime routes, by establishing a line of bases through Hawaii, the Philippines, Java, and Singapore. This concept, therefore,

already existed, and when Japan's expansion concentrated towards Southeast Asia, US war motives were activated. This was also a first maritime defense line envisioned by FDR, and this region, the island defense line discussed here, was simultaneously a major maritime line of communication, thus indicating a strong US willingness to use military force. Consequently, in 1939, the protection of US maritime hegemony and sea lanes, as we conceive it today, led to a project initiated by the Council on Foreign Relations in 1940. World War II had already begun, and through individual studies on economics and finance, security, currency expansion, territory, peace objectives, and politics, they aimed to envision the post-war order. Surprisingly, within a month in 1940, this conception of spheres of influence emerged, initially starting only in the Western Hemisphere. However, this scope within the Western Hemisphere soon expanded.

Initially limited to areas excluding Greenland and Latin America, it expanded within a month to include Greenland and Latin America. Subsequently, it encompassed the entire Asia-Pacific region. By September and October, excluding Soviet neutrality at the time and the regions occupied by Nazis, the plan was to secure sea lanes across all theaters and project military bases to establish an international order capable of crushing any power that threatened the global capitalist economic system or attempted to respond militarily during the Great Depression by projecting naval and air power. This was conceived at that time and, remarkably, was implemented by the United States in and after 1942.

US Conception of Maritime Order and Korea's Role

The Council on Foreign Relations referred to this as the 'Great Area,' and this solidified maritime order, familiar to us today, was established through the Cold War and post-Cold War periods. In conclusion, we can understand the US's current military actions by recognizing that there are regions where the maritime lines of communication do not align with the first maritime defense line, and thus, they are attempting to shift the burden of protecting sea lanes to others. These points are based on my compilation of fleet redeployments.

Therefore, summoning China to the Persian Gulf, which is a Chinese sphere of influence, is an absurd notion. In my opinion, it would be unthinkable if it were a first maritime defense line. Furthermore, from an energy security perspective, dependence on the Persian Gulf has already significantly decreased, and the US has become a net energy exporter. Additionally, from Trump's personal worldview, there was a strong anti-Iran sentiment, and he believed that military interventions should prioritize securing financial benefits over achieving strategic goals. Thus, he might have thought, 'Since we are not dependent on their energy anyway, why should we be cautious here?'

European and NATO Responses and Korea's Challenges

Moreover, Europe already had a multilateral initiative and was conducting operations in the Red Sea. This was an EU operation, Operation Aspides, which already included the Strait of Hormuz within its operational scope. Therefore, France sent one or two more vessels, indicating a willingness to do more, and while the EU and NATO pursued such initiatives, they were not effectively followed up. Regarding IP4, although geographically distant and not directly impacted militarily, they were directly affected in terms of energy security, leading to responses primarily in the form 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 Ryukyus, Taiwan, the Philippines, and Australia. However, in a recent speech by Colby, as noted by Dr. Lee Sung-hwan at the Sejong Institute, South Korea was included for the first time. Upon closer examination, it appears South Korea's inclusion is indeed for the purpose of integrated deterrence, or 'Marina Force Posture.' However, interpretations of this speech by Voice of America still define the primary maritime defense as Japan, the Ryukyus, Taiwan, and the Philippines. Therefore, how we should interpret this aspect is crucial.

Finally, regarding the Taiwan Strait and the South China Sea, where there are similar overlapping areas—a zone that is both a maritime line of communication and a first maritime defense line—there is a possibility of a Chinese maritime blockade. In such a scenario, we need to consider what we should do, both within the framework of the ROK-US alliance and potentially within the NATO IP4 framework, in terms of proactive planning and preparation, especially for a maritime blockade scenario. While an invasion of Taiwan is not immediately anticipated, a maritime blockade is highly probable, and we must consider how to respond. Furthermore, given the considerable possibility of the US using military force in such a situation, I believe further discussion is needed on what we should do and how we should act. With that, I conclude my presentation. Thank you.