Why the U.S Dropped the Atomic Bomb in 1945

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On August 6, 1945, pilot Paul Tibbets took off on a Boeing B-29 to drop the first atomic bomb on Hiroshima. When the Japanese still refused to surrender three days later, the government of the United States dropped another atomic bomb on Nagasaki. An abundance of literature has since focused on the underlying reason as to why the United States chose this course of action. Some theories point to racial influences and domestic pressures, while the two most prominent ones focus on combating the Japanese and asserting dominance vis-à-vis the Soviet Union. International relations’ paradigms serve well to categorize the various explanations and subsequently appraise their validity. It becomes clear, upon assessing these dominant theories through their respective paradigms, that some explanations hold more merit than others.  The revisionist explanation, which emphasizes the showcase of American dominance to the Soviet Union, is evidently the most validated when examined through a Realist paradigm.

Theories emphasizing idea construction and domestic factors commonly circulate in scholarly circles. One explanation to account for this drastic decision highlights the racial elements of the war. It points to widespread American racism toward the Japanese as a sub-human race and accounts for the decision to drop the atomic bomb by theorizing that it was simply a manifestation of this racist mentality (Bastian, “Dropping the Atomic Bomb”). This category of theories falls within the Constructivist framework. Alexander Wendt champions this approach in describing the centrality of interests and identities in the social construction of norms and ideas, which formulate state policy (394-5). Thus, racist notions of Japanese inferiority are socially constructed at the individual level. They are responsible for driving the United States to opt for the decision to drop the atomic bomb. Understood within this framework, several criticisms arise. The fact that the chosen targets were military cities with smaller civilian populations suggests that the United States was not intentionally targeting civilians. Furthermore, the secretive nature of the atomic bomb construction, known as the “Manhattan Project”, could not have elicited the formation of a widespread norm or attitude surrounding the bomb’s deployment. This perspective clearly has considerable shortcomings.

Another group of notable theories stress the pressure exerted on decision-makers by actors within the military-industrial complex. They explain that powerful interest groups couldn’t continue to blindly support the high costs of the Manhattan Project, which necessitated the decision to showcase the bomb’s value (Cooper, “Truman’s Motivations”). These theories fall within an Analytical Liberalist framework. Andrew Moravcsik elucidates this theory in claiming that domestic pressure groups fundamentally impact state preferences (513). Therefore, the military-industrial complex, a powerful wartime lobby group, exerted pressure on the government to drop the bomb as a manifestation of their interests. The military interests center on showcasing the superiority of American military capability and thereby validating their cause, while the industrial interests center around showcasing the value of the bomb so as to substantiate its continued production (Slany, “Special-Interest Lobbies”).

However, the weaknesses of this argument are apparent in interpreting it from an Analytical Liberalist perspective. Historical evidence proves that interests were actually split within these domestic pressure groups, evident in the fact that powerful officials, like Admiral Leahy and General Eisenhower, expressed clear opposition to the prospective decision to drop the bomb (Alperovitz). Moreover, Analytical Liberalism could not explain why there was no domestic pressure to drop the bomb during the Cold War, when military spending rose to a significantly higher level than that which was spent on the Manhattan Project (Shah, “World Military Spending”). Therefore, upon examination of individual and domestic level explanations within the Constructivist and Analytical Liberalist frameworks, their weaknesses and implausibility become apparent. In addition, the Constructivist and Analytical Liberalist approaches are inherently somewhat adept in explaining wartime decisions since norms and domestic pressure groups often exist during times of war and peace. It is also very hard to measure the impact that interests and ideas have on foreign policy, which limits their explanatory value in terms of threat response.

Realism intrinsically provides a more compelling explanation for policy decisions undertaken during wartime. This reality is evident in the central assumptions of all realist theories: anarchy characterizes the international system, states are the primary actors, states seek to maximize power and security and will often utilize force to do so, and states adopt rational policies (Frankel xiv). Kenneth Waltz’s Structural Realism, which emphasizes states’ concern for survival within the systemic balance of powers, is particularly relevant to wartime decision-making. George Kennan confirms Realism’s applicability in elucidating that “The bombings of Hiroshima and Nagasaki illustrate the potential for extreme harm implicit in political realism” (Fernandez 23). Thus, any valuable explanation for the decision to drop the bomb must be adequately explained through the Realist framework.  An examination of the two leading explanations in the scholarly field through Realism provides important insight into their prescriptive abilities.

There is a longstanding debate between traditionalists, who hold that the United States chose to drop the atomic bomb to combat the Japanese threat, and revisionists, who argue that the decision was made to consolidate America’s dominant power position relative to the Soviet Union. Traditionalist accounts are based on the notion that the Japanese government was not willing to surrender. The decision to drop the bomb was undertaken to end the war with Japan without sacrificing additional American lives (Gerson 36). Revisionists question the validity of this assumption on the grounds that the United States acted hastily to drop the bomb without ensuring the viability of other options. They argue that, had the United States truly targeted its policy toward saving American lives, it would have waited to act until it was certain that peace with the Japanese wasn’t possible, and until the Soviet offensive had been carried out. Prior to dropping the bomb, the United States government was aware that the Japanese were making formal requests to the Soviet Union to help them end hostilities. A negotiated peace with the Japanese clearly would have also brought a swift end to the war while salvaging American lives as well. Furthermore, the Soviets announced that they would be ready to involve themselves in the region and attack the Japanese by August 8th, 1945. Allowing the Soviets to carry out their offensive prior to taking action would have also saved American lives.  Revisionists hold that these explanations emphasize the fact that the United States acted to secure its dominance over the region so as to confront the Soviet Union in the post-war period with significant leverage in terms of power and capabilities (Halstead, “Hiroshima 1945”).

Both the traditionalist and revisionist explanations fit well within the broad Realist framework. Both theories focus on states as the primary actors making rational policies. They both adhere to the notion that states seek to maximize power and security in the face of threat. For traditionalists, dropping the bomb seeks to combat the current threat they see in Japan, while revisionists maintain that dropping the bomb seeks to combat the future threat they see in the Soviet Union. The true differences between these explanations are highlighted in their respective applications to the nuances of the Realist paradigm. Kenneth Waltz postulates that the driving factor behind foreign policy decision is states’ drive for survival. States seek to maximize power and security as a means of securing their survival and maintaining their position in the systemic distribution of power (Waltz 85-6). In terms of survival and maintaining the balance of power, the traditionalist explanation falls short of that of the revisionists. Primary documents such as the USSBS publication indicate that Japan would have likely surrendered without the bomb (Alperovitz). Therefore, Japan did not pose a significant threat to the United States’ survival at the point in 1945 when the decision to drop the bomb was undertaken. In addition, Japan was no longer considered a rising power (Alperovitz). As such, it could no longer threaten America’s position in the systemic balance of powers.

In contrast, the United States clearly viewed the Soviet Union as a rising power that needed to be restrained to ensure America’s survival as a superpower (Gerson 27). An examination of the approaches through Realism’s emphasis on the centrality of the system also serves to highlight the superiority of the revisionist explanation. While traditionalists argue that the bomb was dropped to remove the Japanese threat on the systemic level, their approach places too much emphasis on domestic factors like the preservation of American lives.  Revisionism, in contrast, focuses solely on the significance of the system level in claiming that the United States opted to use offensive military capabilities to confront the Soviet Union’s increase in threat. Thus, while both approaches fit into the broad Realist framework, its intricacies are better exhibited through the revisionist explanation.

The unprecedented nature of the decision to drop the atomic bomb elicited a plethora of scholarly arguments that still serve as a point of controversy today. Despite the seeming dissociation of these theories, their explanatory values can be compared and appraised upon their examination within the respective international relations frameworks. Due to Realism’s superior ability to explain wartime decisions than Constructivism or Analytical Liberalism, the most far-reaching theory should complement the Realist paradigm. Although traditionalism and revisionism both conform to the broad pillars of Realism, revisionism displays a more extensive application of the theory’s nuances. Thus, from an international relations perspective, revisionists arguably put forward the most telling explanation as to why the United States decided to drop the atomic bomb.

Work Cited

Alperovitz, Gar. “Introduction: A Personal Note.” The Decision to Use the Atomic Bomb. New York: Random House, 1995. Web. 15 Nov. 2011. <http://books.google.ca/books?hl=en&lr=&id=N8S6Mb26s-QC&oi=fnd&pg=PT1&dq=alperovitz+atomic+bomb&ots=mypaxJLu7w&sig=HtV22Upugksb8ZJLiHe-PYFD4bI#v=onepage&q&f=false>.

Bastian, Peter. “Dropping the Atomic Bomb.” American History for Australasian Schools. Australian Catholic University. Web. 15 Nov. 2011. <http://www.anzasa.arts.usyd.edu.au/ahas/bomb_historiography.html>.

Cooper, John W. “Truman’s Motivations: Using the Atomic Bomb in the Second World War.” 9 Dec. 2000. Web. 15 Nov. 2011. <http://www.johnwcooper.com/papers/atomicbombtruman.htm>.

Fernandez, Frank. “Political Realism Reconsidered.” LBJ Journal of Public Affairs XIII (2001): 23. Web. 15 Nov. 2011. <http://www.lbjjournal.com/system/files/2001_annual_05_Political_Realism_Reconsidered.pdf>.

Frankel, Benjamin, ed. Realism: Restatements and Renewal. London: Frank Cass, 1996. Print. xiv.

Gerson, Joseph. With Hiroshima Eyes. Philadelphia: New Society, 1995. Print.

Halstead, Fred. “Hiroshima 1945: Behind The U.S. Atom Bomb Atrocity.” World History Archives. Hartford Web Publishing, 30 Dec. 2003. Web. 15 Nov. 2011. <http://www.hartford-hwp.com/archives/20/index-dba.html>.

Moravcsik, Andrew. “Taking Preferences Seriously: A Liberal Theory of International Politics.” International Organization 51.4 (1997): 513. Cambridge Journals Online. Cambridge University Press, 18 Aug. 2003. Web. 15 Nov. 2011. <http://journals.cambridge.org/action/displayFulltext?type=1&fid=173204&jid=INO&volumeId=51&issueId=04&aid=173203>.

Shah, Anup. “World Military Spending.” Global Issues. 20 July 1998. Web. 15 Nov. 2011. <http://www.globalissues.org/article/75/world-military-spending>.

Slany, William. “Special-Interest Lobbies.” Gale Encyclopedia of US Foreign Policy. Web. 15 Nov. 2011. <http://www.answers.com/topic/interest-group>.

Waltz, Kenneth. Neorealism and Its Critics. Ed. Robert O. Keohane. New York: Columbia UP, 1986. Print.

Wendt, Alexander. “Anarchy Is What States Make of It: the Social Construction of Power Politics.” International Organization 46.2 (1992): 394-95. Cambridge Journals Online. Cambridge University Press, May 2009. Web. 15 Nov. 2011. <http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=4310164>.


Written by: Hannah Manson
Written at: McGill University
Written for: Prof. Brawley
Date written: November 2011 

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