The International Political Dynamics of the Nagasaki Atomic Bombing: Japan and the Soviet Union from the U.S. Perspective

Viewing the World in a Snow Country: Young People in Sarangbang Embrace Kyushu

Master's student in Diplomacy, Seoul National University

Category: EAI Sarangbang Excursions
Published: February 11, 2025

Master's student in Diplomacy, Seoul National University

I. Introduction

On August 9, 1945, a B-29 bomber carrying a large bomb spotted Nagasaki, a city visible through the clouds. The bomb, "Fat Man," was dropped slightly north of the center of Nagasaki. With a flash, a massive mushroom cloud engulfed the skies over Nagasaki, and the intense thermal radiation melted and destroyed everything in its path. Approximately 70,000 people died in Nagasaki as a result of this attack. The actual death toll was higher, considering the physical and psychological trauma suffered by survivors. After being subjected to atomic bombings in Hiroshima and Nagasaki, Japan declared its surrender on August 15 and officially ended the Pacific War and World War II by signing the instrument of surrender on September 2.

[Figure 1] Above Kyushu, taken before landing

The sky might have looked like this

before the atomic bombing of Nagasaki.

Today, the site of the Nagasaki atomic bombing is marked by a memorial park indicating the drop zone, various monuments, and the Nagasaki Atomic Bomb Museum. The museum contrasts artifacts depicting life in Nagasaki before the bombing with structures showing the devastation afterward, and it also features exhibits on the development of nuclear weapons and their impact, offering a glimpse into the Japanese people's hope for a peaceful world free from nuclear arms to be shared globally.

[Figure 2] A clock at the entrance to the Atomic Bomb Museum exhibition hall

The clock is stopped at the time the atomic bomb was dropped. Given this, what led the United States, the 'aggressor' from Japan's perspective, to drop the atomic bomb on Nagasaki? Two questions arise from this inquiry: first, the lack of relevant documentation, and second, the appropriateness of the means. To begin, there are no detailed government documents explaining the decision to drop the atomic bomb on Nagasaki. While the urgency of the situation might be a factor, it is puzzling that such a critical decision, which could have determined the course of the war with Japan, is not clearly documented.

Furthermore, it is questionable whether the United States absolutely had to drop the atomic bomb on Nagasaki. If the atomic bomb was dropped, there must have been a corresponding objective. If the United States dropped the bomb to break Japan's will to resist, then, in hindsight, it was a mistaken decision, as Japan lacked the capacity to wage war at that point. If the objective was to hasten Japan's surrender, it is somewhat understandable, as the Japanese government did not show signs of surrender even after the first atomic bombing. However, whether it was necessary to cause tens of thousands of civilian casualties to achieve such an objective remains a separate issue. It is questionable whether the U.S. government officials discussed alternative options to secure Japan's surrender without using the atomic bomb.

Could we not, therefore, view the Nagasaki atomic bombing from a broader perspective? Instead of focusing solely on the bilateral relationship between the United States and Japan, could we trace the process of the Nagasaki bombing by considering the international political dynamics of the time? This line of thought led the author to consider the possibility that the Soviet Union had a stake in the U.S. decision to drop the atomic bomb on Nagasaki. Although the Soviet Union was an ally of the United States in World War II, they diverged after the war. The United States then fostered the recovery of Japan, which it had defeated, to use it as a bulwark against the Soviet Union. Therefore, it is difficult to discuss the issue of Japan in the Pacific War without involving the Soviet Union. Examining how the United States viewed Japan and the Soviet Union, respectively, would likely clarify the considerations held by U.S. policymakers during the Nagasaki bombing decision-making process.

There is very little existing research that analyzes the international political dynamics of the Nagasaki atomic bombing in detail. While some studies have approached the Nagasaki bombing from an ethical standpoint, discussing its justification, researchers have primarily analyzed the U.S. decision-making process regarding the atomic bomb by grouping Hiroshima and Nagasaki together (Cummings 1999; Sherwin 2000). Studies analyzing the impact of the United States and the Soviet Union on Japan's surrender also exist, but they do not focus specifically on the Nagasaki atomic bombing incident (Alperovitz 1965; Alperovitz 1995; Asada 1998; Bix 2005; Hasegawa 2005; Maddox 1994; Frank 1999). Therefore, this report aims to supplement existing research on the U.S. atomic bombing and to shed new light on the international political dynamics revealed through this individual event.

This report will proceed in the following order. First, it will examine the discussions within the Interim Committee, where the decision regarding nuclear weapons was made, to understand what the committee members discussed concerning Japan and the Soviet Union. Subsequently, it will focus on other records left by key members of the committee regarding Japan and the Soviet Union, tracing what aspects U.S. policymakers considered concerning Japan and the Soviet Union during the atomic bombing process. Finally, it will explain why the United States had no choice but to drop the atomic bomb on Nagasaki by examining how these considerations were reflected in the actual course of the war.

II. The Interim Committee

1. Formation of the Committee

To understand the process of the Nagasaki atomic bombing, it is necessary to know the thoughts of those involved in the decision. Crucial decisions regarding the atomic bomb were made by the Interim Committee. The Interim Committee was established by Secretary of War Henry L. Stimson with the approval of President Harry S. Truman. The committee was given the provisional name "Interim" because it was intended to discuss nuclear weapons before a permanent body for post-war nuclear management was established (Nuclear Files 2023).

The first meeting, an informal one, took place on May 9, 1945. This meeting served to explain the committee's purpose and functions. In his opening remarks, Stimson stated that the Interim Committee was formed to address the wartime control of nuclear weapons and that the committee's reports and recommendations would be conveyed to the President through him (Nuclear Files 2023). This implied that the committee could exert direct influence on the President regarding the use and management of nuclear weapons.

The committee members can be broadly categorized into scientists, diplomats, and military personnel. The scientific contingent included Vannevar Bush, Karl T. Compton, and James B. Conant. All were affiliated with or subordinate to the Office of Scientific Research and Development (OSRD), established to develop wartime weapons in the United States. Bush headed the OSRD and was the key figure in the development of nuclear weapons under the Manhattan Project. The diplomatic representatives were James F. Byrnes, the President's special envoy, and William L. Clayton, Assistant Secretary of State. Byrnes, who had held significant positions in the previous Roosevelt administration, accepted Truman's request to become Secretary of State before the Potsdam Conference, influencing Truman's decision-making. The military members included Stimson, Assistant Secretary of the Navy Ralph A. Bard, and George L. Harrison, Special Assistant to the Secretary of War and Vice Chairman of the committee.

Subsequently, the Interim Committee convened multiple times, inviting key figures necessary for its proceedings, such as Army Chief of Staff General George C. Marshall and Leslie R. Groves, the overall head of the Manhattan Project. However, the fundamental structure of the committee, comprising experts from science, diplomacy, and the military, remained unchanged. The committee members, each an expert in their respective fields, offered their opinions on nuclear weapons from their unique perspectives to reach a consensus.

2. Discussions on Japan and the Soviet Union

Since the discussions of the Interim Committee played a crucial role in shaping the President's perspective, examining the discourse on Japan and the Soviet Union during the meetings allows us to understand the international political dynamics behind the decision to use the atomic bomb.

Let us first consider the discussions regarding Japan. Two meetings focused specifically on the use of nuclear weapons against Japan: one on May 31, 1945, and another on June 1. The May 31 meeting was where the position on the use of nuclear weapons was finalized. Amidst various viewpoints, a consensus was reached that the nuclear attack on Japan should proceed without prior warning and that the psychological impact on the population was crucial. Dr. Conant agreed, adding that the targets should be military factories or the residential areas of factory workers (Nuclear Files 2023).

However, there were differing opinions on the method of using the atomic bomb. Oppenheimer suggested that a simultaneous, multiple detonation of the bombs was feasible, but Groves opposed this. Groves argued that Oppenheimer's method would make it difficult to gather information on the bomb drop compared to sequential use, that the operation might be rushed and thus ineffective, and that it would not differ significantly from the aerial bombardments already being conducted by the Air Force (Nuclear Files 2023). The opinion that the atomic bomb, which had never been developed before, should not be used like other weapons underscores its immense importance and destructive power. The following day, June 1, participants in the Interim Committee, including Byrnes, urged the War Department to proceed with the nuclear attack on Japan "as soon as possible" (Nuclear Files 2023). This demand stemmed from the belief that possessing and using nuclear weapons could end the war quickly. This is well-illustrated in the statement by the scientific members of the Interim Committee on June 16. Led by Oppenheimer, they recommended to Secretary Stimson that nuclear weapons be used "immediately," citing their obligation to save American lives (Nuclear Files 2023). At that time, the United States was engaged in fierce fighting with Japanese forces until the very end in the Battle of Okinawa. Faced with immense human and material losses due to the war, the United States desired a swift end to the conflict with Japan. Furthermore, as the development of nuclear weapons was nearing completion, the prevailing opinion was that a nuclear attack on Japan was feasible.

Now, let's examine the stance on the Soviet Union. The Interim Committee's discussions encompassed not only enemy nations like Japan and Germany but also allies such as Great Britain and the Soviet Union. Notably, the committee exhibited a degree of caution towards the Soviet Union. The committee's perspective on the Soviet Union is most evident in the May 31 meeting, where the report summarizing the discussions included a separate section on the Soviet issue. The committee members considered the Soviet Union's stance on nuclear control and international cooperation as their "paramount concern." Regarding nuclear development, opinions diverged between the scientific and diplomatic circles. Oppenheimer suggested active exchange and sharing of information with Soviet scientists, while Byrnes was reluctant to share nuclear technology with the Soviets. Nevertheless, everyone agreed with Byrnes's view that accelerating nuclear development would provide a political advantage over Russia. While not ruling out the possibility of cooperation with the Soviet Union, they did not fully trust them (Nuclear Files 2023).

The committee's cautious attitude towards the Soviet Union is also evident in subsequent meetings. In the June 1 meeting, which included invited technical experts, the Soviet Union's potential for technological advancement was discussed (Nuclear Files 2023). Stimson expressed concern about how quickly other countries might catch up to U.S. technological capabilities, and the invited experts responded that Soviet technological progress would accelerate if they acquired German resources, technicians, and scientists. Meanwhile, in a meeting held on June 21, the level at which Truman should address the issue of nuclear weapons to Stalin at the Potsdam Conference was debated. The committee agreed that the President should inform the Soviet leader of the existence of nuclear weapons but should not provide detailed information if the Soviets inquired (Nuclear Files 2023). This reveals the U.S. authorities' desire to maintain a cooperative relationship with the Soviet Union while simultaneously gaining an advantage in the nuclear arms race.

Thus, the Interim Committee explicitly addressed the nuclear attack on Japan while simultaneously viewing the Soviet Union with suspicion. The Soviet Union's actions in the future course of the war were a crucial factor that the United States had to consider alongside Japan.

III. The U.S. Perspective on Japan

1. Selected Targets

The U.S. development of the atomic bomb initially began out of concern over intelligence suggesting that Germany was attempting to develop nuclear weapons. As a belligerent in World War II, the United States, with Germany as an adversary, could not help but worry about Germany's nuclear development, given its world-leading scientific and technological capabilities. However, by 1943, Germany's defeat began to appear imminent. Germany was retreating on the Eastern Front and in North Africa, the Allies had captured Sicily, and in 1944, they successfully landed in Normandy, shifting the war's momentum in favor of the Allies. With Germany's defeat on the horizon, the United States shifted its focus from Europe to the Pacific. An environment was created where attention could be concentrated on Japan instead of Germany. Consequently, the target for nuclear weapons was changed from Germany to Japan.

However, the target was not initially set on the Japanese mainland. While the fundamental use of the atomic bomb against Japan remained unchanged, the nature of the target varied depending on the progress of the war. On May 5, 1943, Groves convened and chaired a meeting of the Military Policy Committee. This committee included Bush and Conant, members of the Interim Committee, as well as Admiral William R. Purnell and Major General Wilhelm D. Styer. The attendees were considering the use of nuclear weapons against Japanese forces. There was a consensus that the first nuclear weapon should be dropped on a Japanese fleet anchorage in the South Pacific, specifically Truk Harbor. At that time, the United States was counterattacking Japan in the Pacific theater following the Battle of Guadalcanal (August 1942 - February 1943), but a direct attack on Japan was considered premature. Therefore, it was deemed appropriate to use the first atomic bomb against the Japanese navy stationed in the Pacific (National Security Archive 2020).1)

In 1945, the United States had almost complete control of the Pacific and was gaining the upper hand in the war against Japan. Consequently, the nuclear attack on Japan began to be seriously discussed. In the first Interim Committee meeting on May 9, Stimson and the committee members read and discussed a report submitted by Groves to the War Department on April 23. Groves's report, which covered the overall aspects of nuclear weapons, was delivered to President Truman, who had recently taken office, through Stimson. In it, Groves mentioned that Japan had always been the target. Furthermore, the report assessed that, unlike Germany, Japan did not possess the capability to develop nuclear weapons. Therefore, by rapidly developing and deploying nuclear weapons against Japan, the United States could not only gain a decisive advantage in the war but also end it quickly (Nuclear Files 2023).

The crucial task now was to select the precise drop zone. The United States entrusted the selection of targets to the Target Committee. The Target Committee, led by Groves, held its first meeting on April 27, 1945. Generals from various branches and scientists engaged in discussions about targets over three sessions. The selection of targets was made during the second meeting on May 12. Cities that met three criteria—being important cities with a diameter of over 3 miles, capable of being destroyed effectively in a single attack, and not having been attacked before August—were Kyoto, Hiroshima, Yokohama, and Kokura. Among these, Kyoto and Hiroshima were classified as the primary "AA" targets, while Yokohama and Kokura were designated as secondary "A" targets (National Security Archive 2020).

The Target Committee emphasized the psychological impact in the use of nuclear weapons. The committee members considered the Imperial Palace, where the Emperor of Japan resided, as a potential target in addition to the four selected cities, aiming to maximize the psychological effect of the nuclear strike (National Security Archive 2020). The United States hoped to break Japan's will to fight with a single atomic bombing. This emphasis on psychological shock was also reflected in the Interim Committee's discussions, as noted earlier.

Malloy believes this was because if the United States had dropped the atomic bomb on Germany, Germany, with its advanced technology, might have acquired nuclear technology.

2. Humanitarian Treatment

However, the use of nuclear weapons was not intended to render Japan irrecoverably crippled. The swift conclusion of the war and the destruction of Japan were separate objectives for the United States. The U.S. desired Japan to remain a viable nation after the war. For instance, George A. Lincoln, who was responsible for strategy and policy in the Operations Department, conveyed his opinion in a report to Hull, then Deputy Chief of Staff of the Army, that Japan should remain "a nation of some weight" in the Far East. John J. McCloy, Assistant Secretary of War, also stated in his report that the complete destruction of Japan should be avoided (National Security Archive 2020).

The U.S. intention not to destroy Japan was also evident in the discussions regarding Japan's surrender. While the United States demanded unconditional surrender from Japan, it was believed that the surrender should not lead to the complete incapacitation of the entire archipelago. On June 28, 1945, Harrison, a member of the Interim Committee, conveyed to Under Secretary Bard his opinion that prior warning was necessary before dropping the atomic bomb on Japan. This was a complete reversal of the decision made by the Interim Committee on May 31, and his justification for this stance was to demonstrate the United States as "a great humanitarian nation" (National Security Archive 2020). Harrison's insistence on prior warning, even to the point of overturning the Interim Committee's decision, and his desire to showcase American morality raise questions about whether there were specific reasons necessitating such measures.

The U.S. humanitarian approach towards Japan is also reflected in the discussions concerning the Imperial institution. On June 29, the day after Harrison's report was submitted, McCloy, the Assistant Secretary of War, argued in a report to Secretary Stimson that the proclamation demanding Japan's surrender should include the preservation of the Imperial institution. He acknowledged that this was the most contentious point but asserted that Japan would not accept surrender if the Imperial institution were abolished. Stimson accepted McCloy's argument. In his diary entry on July 24, during the Potsdam Conference, Stimson noted that he had conveyed McCloy's suggestion—to include the preservation of the Imperial institution in the prior warning to Japan—directly to President Truman (National Security Archive 2020). Although Stimson's request was not reflected in the Potsdam Proclamation, the fact that the United States did not press for the abolition of the Imperial institution after the war suggests that no attempt was made to destroy the spiritual core of Japan.

The Potsdam Declaration, issued on July 26, also demonstrated the United States' humanitarian stance towards Japan. While this declaration, serving as an "ultimatum" to Japan, included provisions for the punishment of war criminals, territorial limitations, and disarmament, it is difficult to conclude that the Allied powers, led by the United States, intended to completely destroy Japan. The Allies explicitly stated in the declaration that they had no intention of enslaving the Japanese people or destroying the Japanese nation and mentioned that Japan could maintain industries necessary for its economic sustenance, provided they were not for rearmament. This stands in stark contrast to the conditions imposed on Germany after World War I through the Treaty of Versailles.

On August 8, the day before the atomic bomb was dropped on Nagasaki, Stimson remarked in a conversation with Truman, comparing Germany and Japan, that Japan should be treated with caution (National Security Archive 2020). What was the reason behind the U.S. desire to treat Japan differently from Germany, allowing it to remain as a normal nation (albeit with limitations)? One reason might be the lessons learned from the post-World War I settlement. France's intention to completely neutralize Germany led to the imposition of conditions that were too burdensome for Germany to bear, resulting in a backlash that gave rise to Nazism. By easing the redline for surrender, the United States may have aimed to guide Japan towards accepting surrender more readily.

Another possibility is that the atrocities that occurred during the occupation of Germany were taken into consideration. During the Allied occupation of Germany, civilian casualties were reported. The Soviet Union, in particular, treated Germany and its inhabitants more harshly than the United States. Soviet forces engaged in looting, executions, and sexual violence against civilians in East Germany, including in the capital, Berlin. While the Soviet Union's desire for revenge could be understood given Germany's unilateral violation of the non-aggression pact and the ensuing war that caused tens of millions of casualties, the Soviet Union's aggressive eastward advance posed a significant burden for the United States. How, then, did the United States view the Soviet Union in the context of the war with Japan? This necessitates an examination of the U.S. perspective on the Soviet Union.

IV. The U.S. Perspective on the Soviet Union

1. Entry into the War

Before the attack on Pearl Harbor, in April 1941, Japan signed a neutrality pact with the Soviet Union. Consequently, the Soviet Union, while part of the Allied powers alongside the United States, did not attack Japan, the enemy of the United States. For the United States, Soviet participation in the war would have provided a significant advantage in confronting Japan. The issue of Soviet entry into the war was finalized at the Yalta Conference in February 1945, where the Soviet Union pledged to enter the war against Japan within three months of the end of the war in Europe.

Within the Truman administration, the opinion that Soviet participation would be a crucial variable in the war against Japan continued to be raised. On June 18, 1945, at a meeting attended by war policymakers, including President Truman, Secretary Stimson, Assistant Secretary McCloy, and high-ranking Army and Navy officers, discussions were held on how to proceed with the war against Japan. Amidst discussions on the prospects and feasibility of an invasion of Kyushu, the attendees focused on the role of the Soviet Union in the landing operations. They believed that Soviet entry into the war could be a "decisive action" in securing Japan's surrender, especially after the Battle of Okinawa, where Japan had already lost hope. Truman agreed with this perspective, stating that the objective of the upcoming Potsdam Conference was to secure the maximum possible assistance from the Soviet Union (National Security Archive 2020).

A report submitted to the President on June 29 also presented the view that the timing of Japan's surrender was related to Soviet entry into the war. In this report, Soviet entry was identified as one of the five factors to consider when conveying the demand for surrender to Japan, specifically mentioning the period immediately after Soviet intervention. The author of the report (believed to be Lincoln) added that although Japan might temporarily resist the Soviet offensive in the early stages, if gradually pushed back by Soviet attacks, the United States' demand for surrender might be positively considered (National Security Archive 2020). Furthermore, the report suggested that it would be ideal if the timing of the U.S. "bombardment operations" coincided with Soviet entry into the war. Next to this phrase, the handwritten note "S1" was added. "S1" was the code name for the atomic bomb then under development. Therefore, the United States intended to subdue Japan by simultaneously employing the international political factor of the Soviet Union and the technological factor of the atomic bomb.

Thus, the United States viewed Soviet participation as a critical factor that could determine the course of the war. They believed that by effectively utilizing Soviet intervention alongside the atomic bomb, the war with Japan could be concluded in a short period. Of course, this scenario was contingent on the Soviet Union acting within U.S. expectations. However, the United States did not consider the Soviet Union a fully trustworthy ally and could not ignore potential risks emanating from the Soviet Union. 2. Manchuria

The issue of Manchuria was the primary concern for the United States regarding the Soviet Union. At the Yalta Conference, Roosevelt partially recognized Soviet interests in Manchuria, including the use of Port Arthur and control of the Manchurian railway, in exchange for Soviet entry into the war against Japan. However, Manchuria was then occupied by Manchukuo, a puppet state established by Japan. If the Soviet Union declared its entry into the war against Japan, it could advance into Manchukuo, a Japanese territory bordering the Soviet Union, which would mean a stronger Soviet influence in China, an ally of the United States under Chiang Kai-shek. Consequently, U.S. policymakers were wary of the Soviet Union's stance on Manchuria.

On June 4, 1945, in a report submitted to Army Deputy Chief of Staff Hull, Lincoln recorded Stimson's following opinion:

If we carry out the declared war aims in the Far East,

we will completely destroy Japan. And in doing so,

we will create a vacuum in the Far East, which Russia will effectively

This removes the means to check it, ultimately allowing Russia to

dominate the region (National Security Archive

2020).

Considering that US policymakers had shown a somewhat humanitarian attitude toward Japan earlier, the conciliatory attitude toward Japan and the vigilance toward the Soviet Union are significant. Regarding Stimson's thoughts, Runkin added his opinion: We have allowed Russia to become a nation that monopolizes its economic system and,

undoubtedly, the most dominant nation in Europe.

We have allowed Russia to take over Manchuria and

vast regions of China, politically and economically, with ease,

(National Security Archive 2020).

The United States viewed negatively the Soviet Union's expansion of its influence in the Far East, given its already dominant position in post-war Europe. Therefore, at the end of the report, it was stated that when setting the conditions for Japan's surrender, the "Russian desires" should be considered along with the Yalta agreement to grant concessions in Manchuria. It was crucial to understand how the Soviet Union perceived Manchuria.

Truman's America viewed even the Soviet Union's acquisition of concessions in Manchuria negatively. On June 6, Stimson left a report detailing his conversation with the President. According to the report, Truman had already been informed by Byrnes about the interim committee meeting on May 31, where key decisions regarding the atomic bomb were made. Truman stated he had received Stalin's promise to recognize Manchuria as Chinese territory, excluding Lushun and Dalian, but Stimson argued that if the Soviet Union were to receive half of the railway control in Manchuria as promised, its dominance there would continue (National Security Archive 2020). Considering the significant discussion of the Soviet Union in the interim committee meeting on May 31, Stimson viewed the possibility of cooperation with the Soviet Union skeptically.

The Soviet Union's acquisition of concessions in Manchuria was also a major topic of discussion within the military. On June 14, Chief of Staff Marshall, in a report submitted to the War Department, stated that the return of Manchuria to China would only be possible with Soviet consent, unless the United States occupied Manchuria. He noted the Soviet Union's pursuit of political, economic, and military interests in Manchuria and mentioned "military operations" for the US occupation of Manchuria (National Security Archive 2020). Although it was deemed unnecessary at the time to deploy US military forces to Manchuria, Marshall's report indicated that the US had considered even a remote possibility of confrontation with the Soviet Union in Manchuria.

In this way, the United States viewed with suspicion the Soviet Union's attempts to expand its influence in Manchuria. If the Soviet Union were to participate in the war against Japan with such intentions, the United States would inevitably feel a significant burden. The US had to continuously monitor the Soviet Union's actions to ensure they did not exceed the level agreed upon at the Yalta Conference. Furthermore, appropriate measures had to be taken to prevent the Soviet Union from overstepping its boundaries.

3. The Open Door Policy

To prevent the Soviet Union from advancing into Manchuria, the United States presented the "Open Door Policy." The Open Door Policy was a policy toward China announced twice by U.S. Secretary of State John Hay in 1899 and 1900, and it served as the cornerstone of U.S. policy toward China until World War II. In 1898, the United States, having won the war against Spain, acquired the Philippines and sought to expand its influence into China. However, China had already become a stage for the competition of great powers since the Opium Wars in the mid-19th century, a trend that accelerated after the defeat of the Qing Dynasty in the Sino-Japanese War.

In response, in September 1899, Hay sent the "Open Door Notes" to Great Britain, France, Russia, Germany, and Japan, demanding that merchants operating in China be guaranteed free and equal trade opportunities regardless of nationality, based on most-favored-nation treatment. The following year, in 1900, the Boxer Rebellion, which aimed to support the Qing Dynasty and expel Western powers, erupted, leading various countries to dispatch troops to suppress the situation. Hay then sent a second note to the countries that had dispatched troops, asserting that China's territorial and administrative integrity must be preserved. This U.S. Open Door Policy was reaffirmed in 1922 when the participating nations of the Washington Conference signed the Nine-Power Treaty.

The Open Door Policy was a policy proposed by the United States, which sought concessions in China, to prevent any single country from exclusively expanding its influence in China. If any country acted contrary to the intentions of the United States, it would be crossing the red line set by the U.S. Japan, a recipient of the Open Door Notes and a signatory to the Nine-Power Treaty, had already invaded Manchuria in 1931, begun invading mainland China in 1937, and directly confronted the United States in 1941. Having its China policy distorted by Japan, the United States could not tolerate another challenger. Therefore, the United States could not overlook the Soviet Union's ambitions in Manchuria, following Japan's actions.

The day before the Potsdam Conference began, on July 16, 1945, Stimson shared with Secretary of State Byrnes the content of his report to the President. The report to the President concerned how to conduct the war against Japan. Regarding the Soviet Union, a party to the conference, Stimson first mentioned the need for a swift final ultimatum to Japan to prevent Japan from seeking a separate peace negotiation with the Soviet Union (National Security Archive 2020). The United States, having deciphered all of Japan's codes, was already aware of Japan's approach to the Soviet Union.

In the report, Stimson stated that there would be no problem as long as the Yalta agreement reached with the Soviet Union in February and the matters to be agreed upon with the Soviet Union at Potsdam aligned with "our traditional policy toward China" (National Security Archive 2020). The traditional policy toward China he referred to was "the Open Door Policy and the recognition of Chinese sovereignty over Manchuria" (National Security Archive 2020). From this, it is evident that the U.S. demand to the Soviet Union was straightforward: the Soviet Union should not treat Manchuria as its own sovereign territory. Given that the United States harbored doubts about the Soviet Union's intentions, the conditions the U.S. could offer to the Soviet Union at Potsdam could not be broader than those at Yalta. Therefore, Stimson's words implied that the maximum limit the U.S. could allow was the agreement reached at the Yalta Conference, and if the Soviet Union did not adhere to it, the U.S. could take extraordinary measures.

Before entering the conference, the United States reaffirmed the terms to be presented to the Soviet Union regarding Manchuria. Stimson emphasized that while the Soviet Union could use Lushun as a military base for a limited period according to the Yalta Agreement, "no special privileges should be granted that would allow Russia to control or restrict trade through Dalian or any other commercial port in Manchuria" (National Security Archive 2020). This particular passage is the only part underlined in the main text of the report, indicating the extreme caution with which the United States regarded any infringement of Soviet interests in Manchuria.

Thus, the United States established a firm red line that the Soviet Union must not cross. If the Soviet Union were to cross the line set by the United States, the U.S. might take action to prevent Soviet southward expansion. The crucial point now was the Soviet Union's stance at Potsdam.

V. From Potsdam to Nagasaki

The Potsdam Conference, held from July 17 to August 2, 1945, was the last official meeting of the Allied heads of state during World War II. The conference discussed how to handle the defeated Germany and the post-war reorganization of Europe, and a joint declaration (Potsdam Declaration) was issued to end the war with Japan. The United States wished to conclude the war with Japan smoothly through discussions with the Soviet Union, but it was difficult to easily shed its existing negative perception of the Soviet Union. The widening gap between the US and the Soviet Union was related to the atomic bomb used by the U.S. in its process of ending the war with Japan. The key to the Nagasaki atomic bombing can also be found here. 1. Parting Ways with the Soviet Union

The Potsdam Declaration, announced at the conference attended by the United States, the Soviet Union, and Great Britain, was issued on July 26. However, the declaration included the names of the United States, Great Britain, and the Republic of China, but not the Soviet Union. From the Soviet perspective, it might have been difficult to declare war on Japan due to the existing neutrality pact. However, at the Yalta Conference, the Soviet Union had promised to enter the war against Japan within three months of the end of the war in Europe. Therefore, with only two weeks left until the three-month period from Germany's declaration of surrender expired, the Soviet Union's failure to declare war on Japan could have raised doubts in the U.S. regarding Soviet intentions. Indeed, the conference revealed that the U.S. and the Soviet Union were pursuing different agendas. Throughout the conference, Truman and his staff repeatedly mentioned the lack of consensus with the Soviet Union, indicating that the two countries were heading in different directions.

Stimson, who accompanied Truman to Potsdam, assisted him closely. His diary entries during the conference vividly reveal the discussions with the Soviets and the thoughts of American policymakers regarding these discussions. Having expressed negative views about the Soviet Union even before the conference, he consistently displayed distrust towards them during the meetings.

On the morning of July 17, the first day of the conference, Stimson mentioned the importance of the Open Door Policy to Byrnes, who was also accompanying the President. He believed that the Open Door Policy would serve as a strong justification to prevent Stalin from seeking commercial rights in Manchuria and advised against granting such exclusive rights to the Soviet Union. Stimson's opinion was conveyed to the President, and on the evening of the same day, Truman informed Stimson that he had "clinched" his position on the Open Door Policy with Stalin during their meeting that day (National Security Archive 2020).

However, Stalin did not yield to Truman's firm stance. According to the diary of Walter Brown, a special assistant to Byrnes, the Soviet Union desired control over Dalian and the Manchurian Railway, which Byrnes found concerning (National Security Archive 2020). The issue of Dalian, in particular, was a headache for the United States. The Soviet Union showed an intention to use Dalian exclusively rather than jointly manage it, which had the potential to conflict with the red line advocated by Stimson.

Consequently, on the 19th, Stimson wrote in his diary that cooperation would be difficult, as the political leaders of the United States and the Soviet Union had different ideas about collaboration. He then contrasted the United States and the Soviet Union, criticizing the Soviet political system and bringing up the topic of nuclear weapons. A nation built upon freedom of speech and freedom in all other respects, like ours,

is increasingly making it clear that it cannot get along forever with a nation where speech is strictly limited and the government

uses an oppressive secret police. This is a matter of great

importance now, and the development of S-1 is focused on this. I feel that our committee, which met in Washington

to discuss this subject and began open communication regarding it with Russia, was conceived in a vacuum (National

Security Archive 2020).

Given that the "committee" mentioned here discussed nuclear weapons and the Soviet Union, it is likely referring to the interim committee. As discussed earlier, during the May 31 meeting, the members of the interim committee exchanged various opinions regarding the Soviet Union, and differing stances emerged. At that time, the United States had not yet made assumptions about the Soviet Union's intentions. However, after directly confronting the Soviet Union at the Potsdam Conference, Stimson stated that their discussions had been "in a vacuum." This indicated that the divergence in positions with the Soviet Union was greater than expected, and the United States began to view the Soviet Union more negatively.

In this situation, the United States began to question whether cooperation with the Soviet Union would indeed help end the war with Japan. Brown's diary entry for July 20 mentions Byrnes's decision to "outmaneuver" the Soviet Union. He hoped for the Soviet declaration of war on Japan during the conference, but as the differences between the U.S. and Soviet views did not narrow, he conveyed to T. V. Soong, Chairman of the Executive Yuan of the Republic of China, that Japan might surrender before the Soviet Union entered the war (National Security Archive 2020). This statement reflected confidence in ending the war with Japan through a means that would overshadow the Soviet Union.

So, how did Byrnes determine that he could "outmaneuver" the Soviet Union? The answer was the atomic bomb. On July 18, Byrnes mentioned that the use of the atomic bomb would be possible in two weeks. Following the successful Trinity test two days earlier on the 16th, his statement was accurate, and this news of success was also conveyed to Truman on the 21st. The United States now possessed a sure means to end the war with Japan unilaterally, excluding the Soviet Union.

A negative view of cooperation with the Soviet Union also emerged within the military. According to Stimson, Chief of Staff Marshall arrived in Potsdam on the 23rd. On the morning of that day, Truman sought Marshall's opinion on the necessity of Soviet assistance in conducting the war against Japan, and Stimson discussed this matter with Marshall. Initially, the United States hoped that if the Soviet Union declared war on Japan, it would "hold up" Japanese forces in Manchuria. However, given the firm Soviet desire for Manchuria, the U.S. concluded that military cooperation with the Soviet Union would be difficult. Marshall told Stimson the following:

Even if we advance in the war without Russia and force Japan to surrender on our terms, this will not prevent Russia from advancing into Manchuria somehow and attacking Manchuria. This would effectively allow them to achieve what they wanted in the surrender terms (National Security

Archive 2020).

Marshall's opinion was conveyed to Truman by Stimson the following day, the 24th. Upon hearing his report, Truman agreed with Stimson's suggestion to remove one of the targets for the atomic bombing.

As Stimson explained earlier, his humanitarian approach towards Japan stemmed from his distrust of the Soviet Union. Although it was clear that the war with Japan needed to end quickly, he argued that the damage inflicted on Japan should be minimized, as discussing cooperation with the Soviet Union in the Far East had become impossible. Stimson explained the rationale for the target deletion to Truman as follows:

If the deletion is not made, the grief caused by such a ruthless act will make it impossible for Japan to reconcile with us

in the long post-war period, even if it means reconciling with Russia. Therefore, as I pointed out, this will prevent our policy, which requires making Japan favorably disposed towards us in anticipation of Russia's invasion of Manchuria (National

Security Archive 2020).

Stimson feared that if the United States dropped a large number of atomic bombs on Japan to end the war quickly, Japan might become closer to the Soviet Union than to the United States after the war, thereby reducing U.S. influence in the Far East. Furthermore, a friendly relationship between Japan and the Soviet Union could open the door for Soviet southward expansion. Therefore, the United States had to find a way to conclude the war with Japan while minimizing Soviet influence.

Ultimately, on July 25, after continuously gathering opinions on the atomic bomb from his staff, Truman gave final approval for the use of the first bomb. According to the plan submitted through the War Department, the first attack was scheduled to occur between August 1 and 10, with subsequent atomic bombings planned for other areas. Although it was a weapon that had to be used to end the war, Truman's mind was not at ease. He expressed his feelings on the day he made the decision in his diary:

We have discovered the most terrible bomb in the history of the world. It may be the destruction by fire foretold in the age of the valley of the Euphrates after Noah and his ark. ... I

do not know what the future holds.

To Secretary of War Stimson, he stated that the military targets and soldiers, and

the Navy should be the targets, not women and children.

He said that even though the Japanese are savages, ruthless, and

insane, we, the leaders of the world for the common good, should not drop

this terrible bomb on the old capital (Kyoto) or

the new capital (Tokyo) (National

Security Archive 2020).

Truman's sympathy for Japan was tinged with the fear that the atomic bomb could lead to the destruction of the human community. If Japan did not surrender, the United States might have to drop another nuclear weapon. This could lead to the complete destruction of Japan, and if Japan harbored resentment towards the United States and entered into peace negotiations with the Soviet Union, it would be the worst decision for the United States, losing both morality and power. Truman did not want such a moment to come.

The Potsdam Declaration was issued on the 26th without the Soviet Union. Due to the Soviet Union's attitude and demands at the conference, it was difficult for the United States to accept them, so the United States had no choice but to break with the Soviet Union at the Potsdam Conference. The United States, seeing cooperation with the Soviet Union as difficult in the war against Japan, intended to end the war with the atomic bomb to prevent further American casualties and thwart Soviet intentions. Above all, Japan's surrender had to precede the Soviet Union's declaration of war. If the Soviet Union entered the war without Japan surrendering, it was a foregone conclusion that Manchuria would fall to the Soviet Union. In other words, the issue of ending the war with Japan was intertwined with the issue of Soviet advance into Manchuria.

2. Soviet Entry into the War and Nagasaki

On August 6, 1945, the United States dropped 'Little Boy' on Hiroshima. In a radio address to the nation, Truman warned that the atomic bomb was dropped to break Japan's will to fight, and if Japan did not surrender according to the Potsdam Declaration, it would face 'a rain of ruin' from the sky (Atomic Heritage Foundation 2022). The United States thus hoped that the dropping of the atomic bomb would lead to Japan's surrender. However, contrary to American expectations, Japan still did not surrender. The Japanese military delayed the surrender declaration, demanding a thorough investigation of the damage caused by the atomic bomb. If this continued, the United States would have to carry out additional nuclear attacks as warned. The key now was when to drop the second atomic bomb.

However, at 5 PM on August 8, Moscow time, the Soviet Union declared war on Japan. The United States was taken aback. This was because the Soviet Union entered the war much earlier than they had anticipated. At the Potsdam Conference, Stalin told Truman that the Soviet army would not be able to move before August 15. Therefore, the Soviet Union's entry into the war seemed possible only on or after August 15. In this situation, the Soviet Union entered the war against Japan a week earlier. The Soviet Union's early entry shows that it was waiting for the opportune moment to engage in war, having completed all preparations. According to the diary of Robert P. Meiklejohn, who assisted the US Ambassador to the Soviet Union, William A. Harriman, Stalin told Harriman on May 28 that the Soviet Union would be ready to move its troops by August 8 (National Security Archive 2020). This was a week earlier than the date mentioned at Potsdam and was the very day the Soviet Union declared war.

The records do not explain why Stalin told Harriman and Truman different dates. However, upon learning that the United States had dropped the atomic bomb on Hiroshima, the Soviet Union could not have asked for a better opportunity. Japan, severely hit on its mainland by the United States, had no capacity to deal with a war against the Soviet Union. In fact, Stalin finalized the date of entry into the war, which had not been confirmed until then, on August 7, the day after the atomic bombing of Hiroshima. Considering that the Soviet army began its advance on August 9, a day after the declaration of war, it is clear that the Soviet Union had already made thorough preparations for the offensive.

The United States found itself in a double bind: Japan had not surrendered despite being hit by the atomic bomb, and the Soviet Union had entered into war with Japan. The idea of an invasion of the Japanese mainland was proposed by military leaders and conveyed to the President, and in diplomatic circles, the prevailing opinion was that the US atomic bombing had hastened the Soviet Union's entry into the war. Therefore, the United States had to end the war quickly, considering both Japan and the Soviet Union. If the war was not concluded, more American lives would be lost in the battle with Japan, and there would be no justification for preventing Soviet advances. In addition, the United States had to prevent Japan from aligning with the Soviet Union in the post-war era, so it had to find the best course of action, considering various conditions. To satisfy these strategic calculations of the United States, it was necessary to use the atomic bomb in a location that would deliver a significant psychological shock to the Japanese people and not threaten the existence of Japan, all within a short period. The target selected after Hiroshima was Kokura. On August 9, a B-29 bomber carrying a plutonium bomb was heading towards Kokura, a city in western Kyushu that had developed heavy industry and had not been subjected to American bombing. However, due to adverse weather conditions, the atomic bomb was dropped on Nagasaki, located south of Kokura. Although smaller in scale than Kokura, Nagasaki was also a major city in Kyushu, and the shock to Japan was considerable.

Although an element of chance was involved, the United States achieved its intended goal with the atomic bombing of Nagasaki. Japan announced its intention to surrender. At 2:30 AM Japan time on August 10, Emperor Hirohito judged that Japan's current capabilities were insufficient to achieve victory against the Allied forces and declared that the war could no longer continue. This news reached the United States, and on the same day, during a US cabinet meeting attended by Truman, Japan's message accepting the Potsdam Declaration was read aloud. At this meeting, Truman stated that he would not use the atomic bomb any further, calling the use of such weapons 'horrible' given that hundreds of thousands of lives had already been lost (National Security Archive 2020).

However, the United States did not succeed in catching both rabbits. While the conclusion of the war with Japan proceeded successfully, preventing the Soviet Union's advance was impossible. Starting at midnight on August 9, Moscow time, the Soviet Union began its advance into Manchuria from three directions. From the Transbaikal Front, Soviet forces entered Manchuria from the west via Outer Mongolia, and from the First and Second Far East Fronts, they entered Manchuria from the east and north, respectively. The United States did not want the Soviet Union to advance further. At a US cabinet meeting on the 10th, Truman stated, "It must be our interest that the Russians do not push too far into Manchuria." Stimson also expressed concern about the Soviet advance and hoped for a swift end to the war, as the Soviet Union could take advantage of this opportunity to advance as far as possible into Manchuria. He even thought that the Soviet advance might not stop at Manchuria and wrote the following in his diary:

The Russians, who have already invaded Manchuria, must be

made to surrender as quickly as possible before they reach

the Japanese mainland. I consider it extremely important

that we secure the mainland before Russia claims any

substantial right to occupy and govern it (National Security Archive 2020).

The United States could not easily determine the extent of the Soviet Union's plans, which were already advancing into various parts of Manchuria. As Stimson feared, it seemed that the Soviet Union could occupy the Japanese mainland if it wished.

The United States believed that Japan's surrender would halt the Soviet advance, but this was not the reality. The Soviet offensive in Manchuria continued even after Japan officially declared its surrender on August 15, and did not end until the 20th. The United States achieved only partial success with the atomic bombing of Nagasaki. Before the atomic bombing, the US intention was to link Japan's surrender with the Soviet Union's advance into Manchuria, but in reality, the two events were independent. As Marshall said, the Soviet advance into Manchuria was not something that the United States could stop.

VI. Conclusion

By reviewing the records left by policymakers, I traced the clues to the atomic bombing of Nagasaki. The conclusion that can be drawn from this is that the atomic bombing of Nagasaki was clearly an international political event. Before using the second atomic bomb, the United States made the decision to use nuclear weapons, considering both Japan and the Soviet Union. The fundamental motive was the swift end of the war, but the US motives towards the two countries were different. Towards Japan, there was a desire to prevent further sacrifice of innocent Americans in a war against an enemy nation. Towards the Soviet Union, there was a strategic calculation to prevent its advance into the Far East. It is unknown which factor had a greater influence on the US decision-making, but the two factors were intertwined.

For the United States, the atomic bombing of Nagasaki was a half success and a half failure. The strategy towards Japan worked, but the strategy towards the Soviet Union did not. The Soviet Union did not halt its advance into Manchuria during the period between the second atomic bombing and the declaration of surrender. It may be a pointless hypothetical, but what if the United States had carried out additional attacks on Japan (not necessarily with atomic bombs)? Would it have led to an earlier official declaration of surrender by Japan and prevented the Soviet advance? It does not seem so optimistic. In a situation where Japan had already indicated its intention to surrender, further attacks on Japan would not have had sufficient justification and, as US policymakers feared, could have led to a catastrophic breakdown in relations with Japan. If Japan had sided with the Soviet Union instead of the United States, the US might have lost Japan itself while trying to defend Manchuria. Furthermore, as repeatedly stated, US military actions would not have been able to stop the Soviet advance. Only the Soviet Union itself could have stopped the Soviet Union.

With the atomic bombing of Nagasaki as a turning point, the United States and the Soviet Union crossed the Rubicon. The two powers that emerged on the world stage were on the verge of collision. Alexis de Tocqueville, a century earlier, predicted what would happen in "Democracy in America".

There are at present on the globe two great nations, which, starting

from different points, seem to tend towards the same end which they

promise to themselves. I allude to the Russians and the English

Americans. ... All other nations seem to have nearly reached their

natural limits; but these are still growing. ... The Anglo-American

G. Tocqueville, Democracy in America, trans. Henry Reeve, rev. Francis Bowen (Cambridge, MA: Sever, 1882), 707-708. The two nations, which had been moving in different directions, eventually met in East Asia, in Manchuria, and in Japan. A new era of international politics was dawning. And at that moment of change, there was Nagasaki.

destiny seems to have been to found a people in some new spot; the Russians seem to be destined to have the whole of the second half of the globe

under their sway. (Tocqueville 2020, 707-708). The two nations, which had been moving in different directions, eventually met in East Asia, in Manchuria, and in Japan. A new era of international politics was dawning. And at that moment of change, there was Nagasaki.

References and Websites

Primary Sources: Atomic Heritage Foundation. 2022. “Truman Statement on Hiroshima”.

https://ahf.nuclearmuseum.org/ahf/key-documents/truman-stat

ement-hiroshima/ (Accessed: December 26, 2024).

National Archives. The President's News Conference.

https://www.trumanlibrary.gov/library/public-papers/94/preside

nts-news-conference (Accessed: December 19, 2024).

National Security Archive. 2020. “The Atomic Bomb and the End of

World War II”.

https://nsarchive.gwu.edu/briefing-book/nuclear-vault/2020-08

-04/atomic-bomb-end-world-war-ii (Accessed: September 14, 2024). Nuclear Files. 2023. “Interim Committee”.

https://web.archive.org/web/20160324162934/http://www.nucle

arfiles.org/menu/key-issues/nuclear-weapons/history/pre-cold-

war/interim-committee/index.htm (Accessed: October 05, 2024). Tocqueville, Alexis de. 2018. *Democracy in America*. Translated by Yong-jae Lee. Paju: Akanet. Secondary Sources: Alperovitz, Gar. 1965. *Atomic Diplomacy: Hiroshima and Potsdam*.

New York: Simon and Schuster.

Alperovitz, Gar. 1995. *The Decision to Use the Atomic Bomb*. New

York: Alfred A. Knopf.

Asada, Sadao. 1998. “The Shock of the Atomic Bomb and Japan’s

Decision to Surrender: A Reconsideration”. *Pacific Historical

Review* 67, 4: 477-512.

Bix, Herbert P. 2005. “Japan’s Surrender Decision and the Monarchy:

Staying the Course in an Unwinnable War”. *The Asia-Pacific

Journal: Japan Focus* 3, 7.

Cummings, Bruce. 1999. *Parallax Visions: Making Sense of

Cummings, Bruce. 1999. Parallax Visions: Making Sense of

American-East Asian Relations at the End of the Century.

Durham: Duke University Press.

Frank, Richard B. 1999. Downfall: The End of the Imperial Japanese

Empire. New York: Random House.

Hasegawa, Tsuyoshi. 2005. Racing the Enemy: Stalin, Truman, and the

Surrender of Japan. Cambridge: Belknap Press.

Maddox, Robert J. 1995. “The Biggest Decision: Why We Had to

Drop the Atomic Bomb”. American Heritage 46, 3.

https://www.americanheritage.com/biggest-decision-why-we-h

ad-drop-atomic-bomb (Accessed: October 15, 2024).

Sherwin, Martin. 1975. A World Destroyed: The Atomic Bomb and the

Grand Alliance. New York: Random House Inc.

Appendix

How Do Nations Remember and Record?

Focusing on the Differing Perceptions of Nuclear Weapons in

the United States and Japan

(USA) National Museum of Nuclear Science & History, Albuquerque

(Japan) Nagasaki Atomic Bomb Museum · Nagasaki Peace Park

Go Ha-eun

Master's Graduate, Department of North Korean Studies, Dongguk University, Major in International Relations

I. Concluding Sarangbang Session 23

The East Asia Institute (EAI) Sarangbang 23, Fall 2024, concluded after its preliminary meeting on Thursday, August 29, 2024, followed by 13 weeks of classes from Friday, September 6, 2024, to Friday, November 29, 2024, and a 3-day/2-night field trip to Japan from Tuesday, January 7, 2025, to Thursday, January 9, 2025.

Reflecting on the EAI Sarangbang 23 sessions, the period from week 1 to week 13 provided a meaningful opportunity to learn and contemplate, following the historical and temporal flow of topics presented by Professor Ha Young-sun, regarding Western IR and IRT versus non-Western IR and IRT, East Asian IR, and Korean IR from various perspectives such as Cold War-Post-Cold War-New Cold War, History vs. Science, and Universality vs. Specificity. Following Professor Ha's suggestion, in addition to the field trip report, I intend to write a comparative travelogue on two sites visited during the summer break of 2024 and winter break of 2025, respectively: the National Museum of Nuclear Science & History in Albuquerque, USA, and the Nagasaki Atomic Bomb Museum and Nagasaki Peace Park in Japan, in relation to the research area of interest, "North Korean Nuclear Weapons."

First, the National Museum of Nuclear Science & History in Albuquerque, USA, and the Nagasaki Atomic Bomb Museum and Peace Park in Japan differ in their approaches to presenting the history and impact of nuclear weapons, based on differing perspectives on nuclear weapons and their use. While the U.S. museum emphasizes the scientific and technological aspects of nuclear science, the Japanese museum focuses on the human suffering caused by nuclear weapons, and the Peace Park serves as a symbolic space for peace and the abolition of nuclear weapons. What is the significance of nuclear weapons in the context of human historical development? The perceptions of nuclear weapons in the U.S. and Japan show significant differences based on each country's historical experiences and political positions, and these also provide insights into the nuclear policies and international roles of both countries as of 2025. Therefore, it is necessary to pay attention to these two locations: the National Museum of Nuclear Science & History and the Nagasaki Atomic Bomb Museum and Peace Park.

II. National Museum of Nuclear Science & History, Albuquerque, USA: A History of Progress

The National Museum of Nuclear Science & History, located in Albuquerque, New Mexico, USA, emphasizes the historical significance of nuclear weapons development and offers diverse exhibitions and educational programs on the progress of U.S. nuclear science and atomic energy technology, generally maintaining a bright atmosphere. In particular, the museum's close ties to Los Alamos National Laboratory, the center of the Manhattan Project and the site where the U.S. first developed nuclear weapons during World War II, made it useful for understanding and acquiring information about the U.S. perception of nuclear weapons.

The National Museum of Nuclear Science & History primarily covers the history of U.S. nuclear weapons development, the scientific and technological aspects of nuclear testing, the advancement of nuclear science and atomic energy technology, and the potential for peaceful uses of atomic energy. It also includes educational aspects regarding nuclear weapons and their effects, as well as warnings about the dangers of nuclear weapons. During my visit in July 2024, I observed many American students visiting the museum in groups, and I was impressed by the exhibition format, which included not only explanations but also interactive experiences related to nuclear science for visitors.

To elaborate further, first, the museum provides various exhibits ranging from the fundamentals of nuclear science to the history of atomic energy development and nuclear weapons development. It was helpful in understanding the scientific and technological progress of nuclear power within the historical context of nuclear weapons development under the U.S. Manhattan Project. I was particularly interested in the content related to Oppenheimer, who is well-known to many Koreans, and focused my attention on this section.

Second, leveraging its proximity to Los Alamos National Laboratory, the museum appears to provide detailed explanations of important data and scientific discoveries related to nuclear tests conducted at the Manhattan Project and nuclear weapons research facilities. It explained, through audiovisual materials, the efforts and achievements of nuclear scientists in how the U.S. developed and advanced nuclear weapons in its early stages. Third, the museum explains not only the military applications of nuclear technology but also its potential for peaceful use in everyday life, illustrating its application in fields such as atomic power plants and medical radiation. This provided an opportunity to contemplate the dual nature (complexity) of nuclear science by simultaneously explaining its peaceful applications beyond military use and its threat.

Fourth, the museum also addresses the risks associated with the development and use of nuclear weapons, including their destructive power and the international, political, and moral controversies surrounding them. Exhibitions on the U.S. use of nuclear weapons against Japan and the Cuban Missile Crisis, among others, included content that examined the impact and repercussions of nuclear weapons from an international relations perspective, prompting reflection on current issues.

My impression upon visiting the museum was that the exhibits, focusing on the development of U.S. nuclear science, the history of nuclear weapons development, and the peaceful application of nuclear energy, along with on-site experiences such as watching videos, participating in quiz games, and other interactive activities, suggested that the U.S. emphasizes nuclear science and technology from the perspective of a "history of progress."

III. Nagasaki Atomic Bomb Museum · Peace Park, Japan: A History of Suffering and Pain

The Nagasaki Atomic Bomb Museum and Nagasaki Peace Park, located in Nagasaki, Japan, serve as sites to remember the devastation caused by the atomic bomb dropped on Nagasaki on August 9, 1945, and to emphasize the horrific suffering caused by nuclear weapons and the importance of peace. The atmosphere was solemn, creating a stark contrast with the U.S. museum.

The Nagasaki Atomic Bomb Museum, in particular, focuses on the devastation caused by the atomic bombing of Nagasaki. It broadly covers testimonies of victims, the impact of the atomic bombing on the Japanese people and related historical facts, the human suffering and damage caused by the use of nuclear weapons, warnings about the dangers of nuclear weapons and their use, Japan's recovery following the atomic bombing, and the peace movement within Japan. The museum provided detailed explanations through photographs and artifacts from the time of the bombing, as well as testimonies from victims. Witnessing the actual detailed accounts and the destructive impact of nuclear weapons left me with a sense of devastation, and the exhibit displaying a melted glass bottle fused with human bone was particularly shocking.

To elaborate further, first, the museum explains the historical context of the final stages of World War II, including the atomic bombings of Nagasaki and Hiroshima. Second, the museum details the devastation following the atomic bombings, emphasizing the moment of explosion and the resulting human suffering. In connection with this, diverse and detailed interviews, photographs, and testimonies from those who died and survived the ordeal were exhibited. Third, the museum presents a critical perspective on the moral and humanitarian controversies caused by the atomic bombings and the use of nuclear weapons, conveying a message aimed at achieving a world without nuclear weapons.

Next, the Nagasaki Peace Park, located near the hypocenter of the atomic bombing, serves as a memorial to the victims of the atomic bombing in Japan and a focal point for the anti-nuclear peace movement. The park features structures such as the hypocenter, peace sculptures, and monuments, providing a space for contemplation on the devastation and dangers of nuclear weapons.

My impression upon visiting the museum and peace park was that, based on Japan's experience with the atomic bombings, the exhibits documenting and explaining the devastation and aftermath of nuclear weapon use, along with the aspiration for a world without nuclear weapons and peace, conveyed a sense of Japan's longing for a peaceful world stemming from the tragic consequences of nuclear weapon use, viewed from the perspective of a "history of suffering and pain." Furthermore, I believe the museum serves the purpose of information provision and education, while the peace park functions as a space for commemoration, making them complementary sites.

IV. U.S. and Japanese Perceptions of Nuclear Weapons from a Korean Perspective: An Analysis

As a student aspiring to research issues related to "North Korean nuclear weapons" from the field of North Korean studies, the National Museum of Nuclear Science & History in Albuquerque, USA, and the Nagasaki Atomic Bomb Museum and Peace Park in Japan were helpful in acquiring information and pursuing personal studies based on the differing perceptions of nuclear weapons in the U.S. and Japan. Moreover, as a Korean, I was able to reflect on how different the situations were in the U.S., Japan, and Korea in 1945, the year of the atomic bombings, and how the relationships between Korea, the U.S., and Japan have changed from that past to the present in 2025, and to contemplate the nature of international relations and diplomacy.

Through my visits to the United States in the summer of 2024 and Japan in the winter of 2025, I was able to directly witness and experience the differing national perceptions of nuclear weapons with greater vividness. First, the National Museum of Nuclear Science & History in Albuquerque, USA, focused on the advancement of nuclear science and technology, particularly the development and testing of nuclear weapons, scientific discoveries during that process, and technological aspects including the peaceful use of atomic energy. Consequently, the museum's exhibits primarily centered on scientific and technological aspects, highlighting the technical processes of atomic energy development and nuclear weapons development. In contrast, the Nagasaki Atomic Bomb Museum in Japan focused on the devastation caused by the use of nuclear weapons, emphasizing the historical event of the Nagasaki atomic bombing in 1945 and the human suffering and damage it inflicted. The museum's exhibits largely featured the horrors of the atomic bombing's impact on Japan, testimonies from victims, and photographs and artifacts. Furthermore, the Nagasaki Peace Park primarily functions as a site commemorating victims of the atomic bombing and conveying a message of peace for the abolition of nuclear weapons within Japan. The Peace Park is characterized by commemorative sculptures and symbols of peace, feeling more like a space centered on memory and commemoration rather than direct exhibits. Additionally, while the U.S. National Museum of Nuclear Science & History begins with the history of U.S. nuclear development and a scientific and technological perspective, the Nagasaki Atomic Bomb Museum and Peace Park clearly differ by focusing on Japan's experience of nuclear weapon devastation and the resulting peace movement.

How do nations remember and record? The U.S. remembers nuclear weapons as a "history of progress," while Japan remembers them as a "history of suffering and pain," and they record this in museums, archives, and peace parks. Based on these differing perceptions of nuclear weapons in the U.S. and Japan, what perception did Korea, as a Japanese colony, hold regarding nuclear weapons in 1945? Considering the situations in Korea, the U.S., and Japan from both past and present perspectives, the context of the end of World War II and the use of nuclear weapons in 1945 feels vastly different from the current situation in 2025, where efforts are being made to strengthen the ROK-U.S.-Japan alliance in response to the North Korean nuclear threat. In the past, in 1945, the U.S. used nuclear weapons, causing immense damage to Japan, and Korea, as a Japanese colony, suffered greatly. The U.S. attacked the Japanese cities of Hiroshima (August 6) and Nagasaki (August 9) with atomic bombs, and Japan, as a victim of the atomic bombings, continuously experienced suffering and pain. Furthermore, during the Japanese colonial period, Japan exploited Korea through various forms of violence and suffering, including human rights abuses, forced labor, conscription, and the comfort women issue. Korea, having suffered from Japanese colonial rule and subsequently division and war, continues to demand reparations and apologies.

In essence, the ROK, U.S., and Japan have each experienced roles as perpetrators and victims based on their respective historical experiences, which remains a significant factor in ongoing diplomatic tensions and international relations. How will the ROK-U.S.-Japan relationship evolve from the past to the present and into the future? <Photos from the visit to the National Museum of Nuclear Science & History, Albuquerque, USA>

Participants: Ha Young-sun, Park Han-soo, Go Ha-eun, Lee Won-ju, Lee Hae-rin, Jung Myung-hyun (6 people)

<Field Trip Preparation Tips from Sarangbang 23 for the Next Cohort> ● Tips Regarding Van/Bus Rental

- If a van or bus is rented for all three days of the trip, the field trip expenses

It can be quite costly. In this case, it may be more economical to rent a vehicle only for the second and third days. (Please calculate the costs with the expedition members before departure.)

- Here are some websites for van rental companies.

https://www.land180.com/korean_japan_bus/%eb%8c%80%ed%98 %95%eb%b0%b4/.

● Tips for booking a bus to Nagasaki

- To reduce the cost of renting a van/bus, we used a highway bus for transportation from Fukuoka International Airport to Nagasaki. If the number of expedition members is small, it is economical to travel to Nagasaki by highway bus on the first day and then use taxis or trams within the city.

- You can book highway buses through the following website.

https://www.highwaybus.com/gp/index. However, if you set the language to something other than Japanese, the bus routes will not be displayed for some reason. We recommend using Google Translate to view the screen in Japanese and proceed with the booking.

- Before the expedition, we planned to take the 12:02 PM bus. However, due to the quick immigration process at Fukuoka Airport, we exchanged our ticket for the 11:07 AM bus on-site. When booking, select the 12:02 PM bus, but if you have ample time after arriving at the airport, exchanging your ticket to travel to Nagasaki quickly is also an option.

● Other Expedition Tips

- The restrooms at the Kyushu Ceramic Museum are beautiful, so we highly recommend visiting them.

- To receive the student discount at the Kyushu National Museum, you need a student ID. Please bring your student ID during the expedition.

- The weather in Kyushu in January can be unpredictable, so we recommend carrying an umbrella.

- In Japan, many famous sites and restaurants may be closed for the New Year holidays, which can last from three to seven days starting January 1st. Please consider this when finalizing your itinerary.

- Taking many photos together will create wonderful memories.

*This text is an AI translation of an original written in Korean. Some translations or nuances may be inaccurate.

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