Introduction
This research proposal aims to examine the Japanese attack on Pearl Harbor, which is considered the greatest intelligence failure in the history of America, at least until September 11, 2001. The historical event remains relevant and important today not only due to its significance but also because it has demonstrated the example of intelligence failure that American society still remembers. After 9/11, intelligence professionals have argued that the situation was similar to Pearl Harbor – even though there were warning signs of an upcoming threat, the most trained intelligence community in the world could not grasp the danger and prevent the attacks adequately.
By implementing a reassessment of events associated with the intelligence efforts surrounding Pearl Harbor, the research implies answering a specific question.
Research question: Despite the abundance of warnings of approaching hostilities in the Pacific, why did American intelligence fail to prevent the Pearl Harbor attack on December 7, 1941?
Answering the research question requires providing an overview of different types of intelligence information that had been provided to the decision-makers in the American government leading up to the attack (Levy 2007). In addition, it is essential to conduct a detailed analysis of the various tactical and strategic indications of warnings that the decision-makers have received before the attack (Bar-Joseph and Levy 2009; Flanagan 1985). Notably, the intelligence failure examination should consider how receptive the decision-makers were toward the warnings provided to them, including the strategic, tactical, and operational failures.
The Pearl Harbor intelligence failure is vital to study even today because the events were ambiguous. The conventional perspective is that intelligence failure typically takes place when the warning signs are available but get lost amidst other information (Carter 1990). Before the 1960s, it was widely accepted that the primary source of strategic surprise was the lack of information about the upcoming threat (Carter 1990). Thus, it was expected that had the US been provided with abundant information about the attack, it would have anticipated and even avoided the attack of the Japanese on Pearl Harbor (McKechney 1963). However, the available information could not be preserved due to the hectic international environment and possibly got limited by different parties’ bureaucratic interests.
Studying the failure of intelligence associated with the attack on Pearl Harbor is essential not only because the event launched the US into World War II but also since it could inform the public about the multi-dimensional nature of intelligence and the circumstances that could lead to its failure. The prerequisites for studying this topic are justified by variable reasons that could affect the inability of American troops to prevent the attack timely. Nonetheless, when assessing the main gaps, scholars note that analytical, organizational, or psychological mistakes are viewed as the causes of intelligence failure (Copeland 2022; Prange, Goldstein, and Dillon 1981). Based on this information, a research hypothesis can be compiled.
Research hypothesis: Ignoring strategic and tactical warnings (independent variables) about the impending attack on Pearl Harbor was the key failure of the American intelligence service (dependent variable).
The issue of decision-makers’ ignorance is disputed by some researchers. For instance, Prange, Goldstein, and Dillon (1981) note that the US military leadership and policymakers were not ready to open hostilities. Nevertheless, it is essential not to dismiss the capabilities of the Japanese to deceive the enemy and surprise them with the attack. Overall, studying a multitude of factors that come into play when discussing Pearl Harbor as an intelligence failure can help answer the set research question.
Preliminary Literature Review
The review of literature on the topic allows for analyzing the issue from different perspectives while taking into account several critical factors that caused the attack. The review can be broken down into the strategic, tactical, and operational intelligence indicators that were available to the decision-makers in America to analyze the responses to relevant indicators. Once WWII had begun, various intelligence sources would be collected, including documents from the prisoners of war, to benefit from press reporting about Japanese diplomatic and political affairs.
Strategic Level Intelligence
From the strategic standpoint, the findings in academic literature demonstrate a large number of critical intelligence indicators provided before the attack. As Wirtz (2006) notes, at that time, the military and governmental leaders should have recognized the severity of the warnings and taken effective precautions to prevent the attack. The first report to mention was the Bloch memo, which was prepared by Rear Admiral Claude Bloch, who commanded the 14th Naval District, which covered Hawaii (Prange, Goldstein, and Dillon 1981). On December 30, 1940, Bloch directed the following message to the Chief of Naval Operations in Washington: “aircraft attacking the base at Pearl Harbor will undoubtedly be brought by carriers” (Prange, Goldstein, and Dillon 1981, 74). This confirms the warnings about the impending threat, which should have been heeded.
The second notable document was the Martin-Bellinger Report made to discuss military planning in the event the attack would take place. The report was dated March 31, 1941, and stated that the Japanese air force could appear in Hawaii without warning from the intelligence and that “it appears that the most likely and dangerous form of attack on Oahu would be an air attack” (Shafter 1945, 349). The third important report was the Farthing Report, which argued against complacency and stated that plans based on the conviction that Hawaii was the strongest outlying naval base and could withstand attacks were “inherently weak and tend to create a false sense of security with the consequent unpreparedness for offensive action” (Prange, Goldstein, and Dillon 1981, 65). Thus, there were official warnings of a potential attack by the Japanese army.
Tactical Level Intelligence
In addition to strategic issues, some researchers offer to consider tactical gaps. The first tactical level indicator relevant to the intelligence surrounding the attack was “The Bomb Plot Message,” which was the note sent by the Japanese Foreign Ministry on September 14, 1941 (Wohlstetter 1962). In the message, the Honolulu consulate was asked to provide a detailed report on the ships present at Pearl Harbor (Wohlstetter 1962). A later message, dated November 15, directed the consulate to make similar reports twice a week and divide the Pearl Harbor waters into five sections to give feedback on the positioning of warships and carriers (Wohlstetter 1962). Notably, the Washington intelligence agencies did not inform military leaders in Hawaii about these notes, which was an omission.
Another significant event occurred on December 7, the day of the attack. Opana radar operators noticed a group of aircraft that appeared 137 miles north of Oahu (Wohlstetter 1962). When the operators reached Lt. Kermit Tyler, an Air Corps officer in training that was available on the shift, he told them that the planes were a flight of American B-17 bombers that were expected to return from the mainland that morning and said that the privates could forget about it (Wohlstetter 1962). Even though Tyler tracked the aircraft further, he later confirmed that the planes were navy bombers that were practicing at Pearl Harbor (Wohlstetter 1962). As a result, these tactical failures are crucial to note in the context of the overall intelligence failure.
Theoretical Framework
The theoretical framework represents the structure that may hold or support a theory of a research study. It is intended to introduce and describe the theory that can explain why the research problem under study exists. The study will be focused on the theory of intelligence failure. The concept discusses the presence of various paradoxes that take place within units of intelligence and do not allow eliminating risks and attacks (Betts 1978). According to Betts (1978), intelligence failures are not only inevitable but also natural. This is due to the fact that such omissions are rather the causes of political and psychological gaps than analytical or organizational ones (Betts 1978). Therefore, the concept of intelligence failure is relevant to studying the issue in question.
The research proposal argues that the intelligence failures that occurred during Pearl Harbor are still relevant today. Therefore, Betts’ (1978) notes about the theory of intelligence failure are sound and can be applied within the context of the twenty-first-century challenges. His article was written in the wake of the Vietnam War and the reforms of the United States Intelligence Community after the inquiries of the Church Committee (Betts 1978). Even though the theory of intelligence failure includes considerations of the causes of omissions, areas of gaps, as well as imperfect solutions, the discussion of the theory itself occurs within a particular time and space.
While drawing from the theoretical framework, the qualitative research design suits the goals and objectives of the study. As Little (2016) remarks, in the context of the historical event associated with an intelligence failure, the qualitative design may help describe and examine past events to understand the present and anticipate potential effects on the future. Koshinsky (2021) states that there is currently an abundance of qualitative information on the Pearl Harbor intelligence failure. Due to a systematic literature review, it will be possible to identify, select, and critically appraise the available evidence to answer the question that has been formulated.
Preliminary Conclusion
To summarize, the mistakes that the decision-makers of the US intelligence team made during the Pearl Harbor events remain relevant for analysis today. There were strategical and tactical warnings of the upcoming attacks, but the decision-makers did not take them seriously, which resulted in the intelligence failure. Since such omissions take place regularly, which is evidenced by the concept of intelligence failure, this is essential to find out how teams should act to ensure that decision-makers respond to the warnings that the intelligence team discovers and delivers.
The attack on Hawaiian Pearl Harbor is one of the most tragic pages in recent American history. The Japanese forces launched an attack on the United States at Pearl Harbor on December 7, 1941, which devastated the American troops and caused up to 3,500 casualties (Russett 1967). As a result of the attack, the United States launched itself into World War II. Today, the event is notable not only due to its historical significance and context but also as an example of intelligence failure. Historians have presented different explanations for why the intelligence available to the decision-makers did not prevent the attack (Russett 1967). There are contradictory opinions; some blame the intelligence community for failing to analyze the crucial sign of the attack prepared by the Japanese, while others accuse the military commanders who were unprepared to respond (Betts 1978; Wohlstetter 1962). Therefore, the objective prerequisites for the tragedy are worth studying.
This research is aimed at conducting a systematic review of relevant academic literature to answer the question of why American intelligence failed to prevent the attack on Pearl Harbor in 1941. After synthesizing the primary and secondary resources on the defined topic, it was found that it was not the intelligence failure per se that caught the American Navy off-guard during the attack but rather the inability of decision-makers to use the intelligence information effectively. While there were gaps in tactical intelligence, there were plenty of strategic indicators pointing to the fact that war could affect Hawaii suddenly, and the political and military leaders disregarded those signs.
Thesis statement: The intelligence failure in the time leading to the Pearl Harbor attack occurred due to the poor understanding of how the information could be disseminated to ensure its effective application.
Literature Review
Intelligence Failure
The incorrect or inadequate interpretation of the data is one of the critical causes of the tragedy. Betts (1978) places the failure of intelligence on the shoulder of the consumer of the information. The scholar states that the most vital mistakes have rarely been made by the ones who collect raw information, “occasionally by professionals who produce finished analyses, but most often by the decision makers who consume the products of intelligence services” (Betts 1978, 61). The theorist suggests that there is no room for improvement for intelligence institutions, and failure is caused by psychological and political factors rather than operational gaps (Betts 1978). Importantly, Betts (1978) argues that improvements can be made in the analytical processes while paying attention to the political and psychological challenges at play. Even though the empirical study of intelligence failures has been well-developed, the lessons are not always learned from the mistakes.
Thus, even in instances when the intelligence process is perfect and provides abundant information to decision-makers, the consumption of the intelligence can never be perfect because there are psychological limitations and political factors. In Betts’ (1978) theory, this is essential to locate the gaps between information analysis and decision-makers’ approaches. Importantly, there are three pathologies of intelligence that are the most prominent, such as during attack warnings, operational evaluations, and defense planning (Hanyok 2008). An essential challenge in providing warnings of attacks is the inherent problem of discerning and predicting the intentions of an enemy timely. Pearl Harbor is an example of a major surprise attack in which the evidence of the intended action existed but was not passed sufficiently quickly through different tiers of management to reach decision-makers in time and prevent the disaster.
Assessment of Strategic Level Intelligence
During the time before the attack, several strategic intelligence indicators were collected, with the evidence pointing to the fact that the Japanese had been planning a military offense. Importantly, on November 1 and December 1, 1941, the Japanese changed 20,000 of their radio signs, which made it more difficult for American intelligence to read message traffic (Wohlstetter 1962). This was an indicator of hostile activity preparation which would likely occur on a larger scale, as reported in the 14th Naval District intelligence summary (Prange, Goldstein, and Dillon 2014). As a result, the implications of the attack showed the unpreparedness of military decision-makers to evaluate intelligence data.
The loss of contact with Japanese carriers in mid-November 1941 is another indicator of the possible attack. As Hanyok (2008) claims, the US analysts could not agree on where they were likely to be located. In addition, there were deadline messages sent by Tokyo to its Washington embassy in November 1941, warning the diplomats that a deadline had been set on November 29 for concluding negotiations with the United States (Hanyok 2008). After the deadline, Tokyo stated that “things are automatically going to happen” (Hanyok 2008, 190). However, these statements were not taken with all possible seriousness.
Ignoring Japanese messages led to active actions on their part. After the deadline, on December 1 and 2, the officials at Tokyo ordered several of its diplomatic posts in Asia and those in Washington and London to get rid of their codes and code machines, with the intelligence about this sent to Hawaii on December 3 (Prange, Goldstein, and Dillon 2014). As to last-minute signals, an important event was the “pilot message” sent on December 6 to the embassy in Washington that Tokyo would send a reply to the latest American proposals in fourteen parts (Wohlstetter 1962). The parts of the message were intercepted by Americans and forwarded to Washington by teletype as soon as they were received, mainly throughout the morning and the afternoon. Notably, the last part did not come until 3:00 in the morning on December 7, which was the message to the Japanese ambassador to submit a reply to the US government at 1:00 p.m. on December 7 (Ikuhiko 1994). The order was followed by the next message to destroy all documents after deciphering incoming messages.
Considering the reporting available to Senior Army and Navy intelligence officials, who had the full picture of all available reporting, it was clear that war was imminent in the Pacific, although there was no expectation that it would be aimed at the US. The common conclusion was that the hostilities would start with the attack of the Japanese to the south toward Thailand (Wohlstetter 1962). It was expected that after seizing control or occupying Thailand, the Japanese would immediately attack British possessions in Singapore and Burma (Wohlstetter 1962; Hanyok 2008). The US officials concluded that either war or the rupture of diplomatic relationships with Japan was inevitable (Ikuhiko 1994). Even though the Chief of Naval Operations, Admiral Stark, had prepared a warning for the US fleet, it was not sent because the superiors felt that the previous warnings were sufficient (Ikuhiko 1994). This overconfidence was misguided, given the clear signs of an impending threat.
Assessment of Tactical Level Intelligence
From a tactical perspective, several factors should also have been taken into account when evaluating the upcoming events in Hawaii. The “Bomb Plot message” was a significant indicator entailing the event on September 14, 1941, of the Japanese Foreign Ministry contacting the Honolulu consulate and asking for a detailed report on ships stationed at Pearl Harbor (Butow 1996). Importantly, the consulate asked to divide the waters into several areas to make the reporting more efficient, while the intelligence agencies in Washington did not mention this to Hawaii’s military commanders (Butow 1996). After the attack, the message exchange between the consulate and the foreign ministry became known as the bomb plot message and was later cited in congressional investigations as a crucial warning of the attack, which had been missed.
The Opana radar plot is another tactical-level intelligence sign that was not taken seriously. At various points around Oahu, truck-mounted radars were set up, with one position being the northern top of Oahu, at Kahuku Point, which was referred to as Opana (Wohlstetter 1962). Early in the morning on December 7, the operators noticed an unusual occurrence on their screen – a group of aircrafts approaching Oahu in the range of 137 miles (Wohlstetter 1962). The operators reported the occurrence to Lt. Kermit Tyler, an Air Corps officer in training who guessed that the aircraft was most likely the American B-17 bombers that were in bombing practice, which he later mentioned in his report (Wohlstetter 1962). What the operators and Tyler failed to consider the spotting of Japanese bombers.
The upcoming hostilities were not perceived seriously by military leaders. When responding to the tactical level intelligence indicators, the Navy intelligence officers stationed in Hawaii felt that the war would soon arrive with Japan (Wohlstetter 1962). Nevertheless, similar to their Washington-level counterparts, they agreed that the Japanese were incapable of implementing an attack on Pearl Harbor (Hamblet 1995). This agreement was most poignantly expressed in an exchange between Admiral Kimmel and LCDR Edwin Layton, the Fleet Intelligence Officer (Lambert and Polmar 2003). Because the Japanese Navy had changed its call signs, most analysts believed that the fleet carriers were likely in home waters, with Layton reporting, “Unknown – home waters?” (Lambert and Polmar 2003, 79). To this, Kimmel replied, “What! […] you are the Intelligence officer of the Pacific Fleet and you don’t know where the carriers are? […] For all you know, they could be coming around Diamond Head, and you wouldn’t know it?” (Lambert and Polmar 2003, 79). Later, Layton testified that he wished he had considered the possibility that the Japanese carriers were under radio silence approaching Oahu. Thus, the level of tactical intelligence proved to be ineffective.
Receptivity Toward Intelligence
Given the availability of strategic and tactical indicators that the Japanese had been planning an attack on Pearl Harbor, there was no unity among the Washington officials that the naval base would be attacked. Despite the warnings of the possibility of a surprise attack on Hawaii, military leaders discounted the threat, referring to it as a rumor (Dahl 2013b). For instance, Admiral Harold Stark, the Chief of Naval Operations, wrote a memo to the Pacific Fleet’s Commander in Chief, stating that his division “places no credence in these rumors […] No move against Pearl Harbor appears imminent or planned for in the foreseeable future” (Dahl 2013a). Such a statement testifies to the misinterpretation of critical intelligence data.
The majority of senior staff and operations officers shared the confidence that no attack would take place and thus were dismissive toward those who expressed more significant concerns. Such a view was described by Layton, who stated that the following Sunday after November 29, he expected a crisis to occur (Dahl 2013a). That Sunday passed without any incident, and on Monday, he was greeted with mocking statements: “What happened to your crisis, Layton? Layton and his Sunday crisis” (Dahl 2013a). Notably, Kimmel and other senior advisors were sure that the attack would not take place and noted that “the only signal that could and did spell ‘hostile action’ to them was the bombing [of Pearl Harbor] itself” (Dahl 2013a). As a result, important nuances indicating the upcoming hostilities were not analyzed effectively by the command.
Methodology
The research implies conducting a systematic review, which is a critical and reproducible summary of the results of the available research on the topic of intelligence failure during the Japanese attack. The chosen variables are strategic and tactical warnings about the upcoming attack (independent variables) and the failure of the American intelligence service (dependent variable). The main challenge of the chosen methodology is to identify all studies relevant to the current research question (Snyder 2019). At the stage of planning, before the systematic review of articles, the statement on the inclusion and exclusion criteria should be made (Patino and Ferreira 2018). The exclusion criteria entail online magazine articles, blog posts, and other non-peer-reviewed sources available online. The inclusion criteria for the systematic review entail peer-reviewed articles and primary sources, such as books, essays, and conference proceedings covering the topic of intelligence failure that led to the Pearl Harbor attack.
The criteria for inclusion do not consider the dates of publication as essential defining criteria because Pearl Harbor was a historical event and the research published closer to its occurrence remains relevant. However, most of the studies that are included in the review were published a few decades later after the attack because they synthesized historical information from an abundance of sources. It is essential to mention the resources that include information from primary sources, such as quoted data from those who witnessed the events.
To find this information, the snowball sampling method has been implemented. It entails tracking down references or citations in different documents. The snowball method is a mechanism of finding literature by using key documents on the subject as a starting point (Wohlin 2014). To search for the relevant pieces of information, different resources have been screened to find as many mentions of primary data as possible. Snowball sampling is the most appropriate method for locating the studies for the systematic review because the searches through databases only provide peer-reviewed articles (Hiebl 2021). To find primary sources, the screening of those articles has been conducted. Titles and abstracts of electronic search results have been checked to identify the studies that are relevant to include in the systematic review, with the emphasis placed on the intelligence during Pearl Harbor and not the historical event in general.
In terms of the validity of the chosen methodology, systematic reviews represent an important source of valid evidence. They allow for identifying, appraising, and synthesizing the available information on the topic in question (Verdejo et al. 2021). Since the inclusion and exclusion criteria are clearly defined, the applicability of the gathered data gives sufficient information for judging the external validity and applicability of the findings.
The implemented methodology had both strengths and some limitations. The main barrier is the selection bias caused by snowball sampling, which is a non-probability technique (Raina 2015). In addition, because this sampling type does not select articles for review based on random selection, this is impossible to determine the potential sampling error and make statistical inferences from the sample (Sharma 2017). Addressing the limitations that come with the purposive sampling of research is not possible because the articles included in the systematic review have to fit the selection criteria, and choosing them randomly is not an option.
Analysis and Findings
The systematic review of the literature proves the hypothesis that the failure of American intelligence associated with Pearl Harbor warnings entailed the inability of decision-makers to respond to the warnings of the threat. The technologies used for maintaining high levels of intelligence were utilized for gathering data on the Japanese. However, the challenge was not in the inefficient use of espionage technologies but rather in the inability of some commanders, who pursued a middle policy between confrontation and appeasement, to provide adequate responses to the warnings of the upcoming attack.
Even though the US Navy had a history of war games and drills focusing on the threat of the Japanese surprise attack, the Operational Commanders did not take the danger of the attack on Hawaii as serious (Coox 1994). Importantly, Kimmel’s exchange with Layton about the missing plane carriers meant that they both were aware of at least a remote possibility that the Japanese attack could take place (Stillwell 2016). The fact that operation officers mocked Layton for the “Sunday crisis” means that the majority of the senior advisors in Hawaii were quite confident that no surprise attack from the Japanese would take place (Stillwell 2016). Therefore, there were no problems with long-range strategic intelligence because the leadership, both in Washington and in Hawaii, understood that sooner or later, a war would break out with Japan (Hanyok 2009). Thus, even though the intelligence officials were charged with estimating the threat, they did not firmly believe that the Japanese would have the capability to launch a long-distance attack.
Therefore, intelligence itself was not responsible for the failure to predict and prepare for the Pearl Harbor attack. Rather, the lack of belief in the seriousness of the threat on the part of crucial decision-makers in the US was the defining factor that led to the failure. Samuels (2019) suggests that the disbelief was attributed to the lack of specific, tactical signs. However, as the systematic review has shown, there were some tactical warnings that could have been further analyzed and considered during the decision-making. Therefore, the overall lack of receptivity toward intelligence on the part of senior leaders was the main issue.
In the presence of sufficient intelligence indicators, they were misunderstood and even ignored as a result of the improper analysis. Even though there were some gaps in intelligence, particularly in the tactical indicators, the failure of receptivity was the key cause of the unpreparedness of Americans for the attack (Dahl 2011). Moreover, it is unlikely that even better intelligence of a tactical level would have been needed to prevent the Pearl Harbor bombing (Grabo 2004). Some of the warnings were accurate, but since they were based on strategic level intelligence, the decision-makers did not take them as viable signs that called for the Navy to get better prepared for the upcoming attack.
Conclusion
The reassessment of the intelligence events leading up to the attack on Pearl Harbor provides the implications both for the theoretical understanding of intelligence failure as well as for the practical efforts necessary to prevent surprise attacks from occurring in the future. Indeed, before the attack, there was indeed a great deal of intelligence available that warned decision-makers about the possibility of Japanese aggression in the Pacific. Intelligence failures do not always result from the lack of information but rather stem from the inability of decision-makers to respond to the information collected effectively.
Drawing from the examples of the available tactical and strategic warnings leading up to the attack, the study can conclude that the intelligence failure took place because the decision-makers did not consider the incoming information to be worth analyzing. This means that to avert similar failures in the future, more efforts should be placed on the issue of receptivity. The intelligence community should have developed closer connections with senior officials and policymakers who made crucial decisions. Future research may focus on evaluating the US military doctrines prior to World War II and comparing them with those adopted after the attack on Pearl Harbor, including both strategic and tactical methods of warfare.
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