1 The Cambodian Civil War and the Paris Peace Agreement

Although Cambodia became independent from France in 1953, the 1970 coup plunged Cambodia into a civil war that lasted for more than two decades. In the late 1970s, the Khmer Rouge (the Pol Pot-led radical communist faction) seized the country to establish a regime of terror. Even worse, the civil conflict gradually developed into a proxy war between China and Vietnam, resulting in the Vietnamese incursion of Cambodia. This eventually led to the collapse of the China-sponsored Khmer Rouge regime in 1979, although internal conflict continued between the pro-Vietnam Heng Samrin faction and the tripartite anti-Vietnam alliance, including the remnants of the Khmer Rouge , the Prince Sihanouk royalist faction, and the anti-communist Son Sann faction (Country Watch, n.d.).

In 1989, the end of the Cold War led to the withdrawal of Vietnamese troops and added momentum to finally conclude the civil war that had raged in Cambodia for two decades. In 1990, Japan hosted a Cambodian peace conference in Tokyo, which ultimately led to the signing of a negotiated “Paris Peace Agreement” in 1991 (United States Institute of Peace, 2000). The peace agreement involved Cambodia’s four major warring parties, namely the Khmer Rouge , Heng Samrin , Sihanouk, and Son Sann factions, as well as 19 concerned countries. It laid the foundation for post-conflict statebuilding anchored in a general election for a new government as well as the creation of a UN transitional authority, or UNTAC, which was charged with implementing the election. The four signatory parties agreed to a permanent cease-fire and made disarmament commitments while also accepting that these plans would be overseen by UNTAC.

Having been reluctant to participate from the very beginning, the Khmer Rouge virtually withdrew from the peace agreement soon after it was signed. Due to their substantive retreat from the peace process, Cambodia was again dragged into violence even while the formal peace agreement remained intact. During the mission’s one-and-a-half-year duration, the Khmer Rouge continued to threaten UN peacekeepers and civilians working for UNTAC. Despite the de facto collapse of the cease-fire agreement, UNTAC continued to be operated to implement the general election on time, widening the gap between the legal framework and the harsh reality on the ground.

2 International Legitimacy of UNTAC

2.1 Statebuilding Under the UN Transitional Authority

To implement the Paris Peace Agreement, UNTAC was established in February 1992 following UNSCR 745 under the leadership of the SRSG Yasushi Akashi, a high-ranking Japanese UN official. UNTAC was one of the most representative examples of multifunctional PKOs in the 1990s (see Chap. 1). It was assigned a very ambitious role as a transitional authority supporting the foundation of a new Cambodian government. To achieve this, UNTAC was mandated with various duties for both restoring peace and running the civilian administration (e.g., refugee repatriation support). UNTAC’s most important task was to conduct a general election safely and on time in May 1993. To carry out its multipurpose assignments, UNTAC was established as the largest multifunctional peacekeeping mission ever, staffed by nearly 20,000 uniformed personnel (including both military troops and civilian police) and several thousand civilians (UNDPO, n.d.).

2.2 The Challenges in Implementing the Cambodian General Election

Despite high aspirations, UNTAC was troubled by the Khmer Rouge , which continued to resist the peace accords. Facing increasing insecurity, UNTAC stepped into higher-risk duties beyond its authorized mandates. In other words, peacekeepers—both troops and civilian police officers—were unexpectedly assigned more dangerous tasks without prior preparation and with no legal basis. Tensions continued to escalate ahead of the upcoming general elections, which were scheduled for May 1993. Increasing insecurity and public anxiety motivated UNTAC to act even in the absence of a new authorized mandate. More peacekeepers—both military and police personnel—were assigned to combat the security threats posed by the Khmer Rouge . Not surprisingly, the number of peacekeeper fatalities soared, risking damage to UNTAC’s overall credibility. Regardless, the general election was held without serious disturbances (Findlay, 1995), and a new government was subsequently formed. Despite numerous challenges, UNTAC achieved its most important goal, and this success enhanced trust from international society.

3 Political Background to Japan’s UNTAC Participation

3.1 Momentum Toward “International Contribution”

This section considers the topic of Japan’s personnel contribution to Cambodia. The 1991 Gulf War rapidly instilled a sense of humiliation in Japan, both in the government and in society, because many Japanese believed that Japan’s lack of military contribution to the multinational force was being derided by international society (see in Chap. 2). In truth, it was not clear to what extent the world really noticed the lack of Japan’s military presence, aside from the furious US government. However, this bitter memory left the so-called Trauma of the Gulf, or the political obsession with contributing troops for international peace and security, which was quickly encapsulated in the political catchphrase “International Contribution.” This was not an official term adopted by the GoJ, but was often heard in more casual usage, such as in journalism and informal political discussions. The phrase was not precisely defined and vaguely implied a wide range of commitment and cooperation to the international society, yet it was generally understood that the concept included military deployment to support international peace and security.

Against this backdrop, the GoJ, led by Prime Minister Kiichi Miyazawa, devised a firm solution of enacting a new law to authorize SDF dispatch to UNPKOs. Despite vocal anti-military resistance both in the Diet and from society, the PKO Act was finally passed in June 1992 (see Chap. 2). The GoJ was determined to immediately contribute the Japanese peacekeepers to a UN mission. It was considered vital to exhibit to the international society that Japan had taken a step forward under the political catchphrase of “International Contribution” (see Chap. 3). For this purpose, UNTAC had been envisaged from the beginning of the lawmaking process as the first destination for SDF deployment to a UNPKO. When the PKO Act was finally passed, UNTAC had already been operational for four months, which motivated the GoJ to begin urgent preparations to dispatch the SDF to Cambodia.

3.2 Strengthening Japan’s Political Role in Southeast Asian Diplomacy

The motivation behind Japan’s participation in UNTAC can also be understood from the perspective of Southeast Asian diplomacy. Since the advocation of the “Fukuda Doctrine” in 1977, the GoJ had attached great value to its relations with neighboring Southeast Asian countries (Kano, 2020, pp. 9–13). Since the announcement of the “International Cooperation Initiative” in 1988, the GoJ had a strong incentive to support peace initiatives in developing countries, especially through diplomatic efforts. With the combination of these elements, the GoJ became actively involved in the Cambodian peace process by hosting a peace conference in Tokyo in June 1990 (MoFA, 2007; Kuriyama, 2016, pp. 189–191; Murakami, 2001; Murakami, 2007, pp. 131–138). Along the same lines, the GoJ was strongly motivated to enhance its assistance to Cambodia by contributing personnel, including the SDF, as part of UNTAC.

4 Legal Foundations of Japan’s Participation

4.1 The GoJ’s Insistence on Upholding the Five Principles for Participation

While the Japanese delegation was deployed to Cambodia, it seemed highly doubtful that the stringent Five Principles were being fulfilled in the field (see Chap. 2). It was almost inevitable that domestic controversy would be provoked over whether it would be appropriate to dispatch the SDF as part of the UNTAC mission. The GoJ, however, insisted that the conditions in Cambodia met the prerequisites necessary to allow SDF deployment according to the Five Principles.

First, as seen above, a cease-fire agreement had been made among the four warring parties prior to the establishment of UNTAC. Second, those parties had also consented to the deployment of the SDF. Third, the scope of the SDF’s operations in Cambodia was narrowly restricted only to logistical support, such as engineering works, and unarmed cease-fire-monitoring services. Fourth, SDF peacekeepers were allowed to use weapons only to the minimum extent needed for self-preservation. Fifth, Japanese troops were to be deployed to the Cambodian city of Takeo, which was in a relatively safe area in the south. Despite satisfying these five conditions at the beginning of the dispatch, however, the local situation grew increasingly volatile. Greater insecurity jeopardized these prerequisites, which threatened to violate the Five Principles, meaning that SDF peacekeepers might have to immediately withdraw from Cambodia.

4.2 Problems Related to Tight Restrictions on Weapons Use

The “use of weapons” issue entailed another difficult problem. The PKO Act authorized a decision to fire at the discretion of each individual SDF member, despite the fact that military personnel are generally supposed to fire only under the orders of a commander. This inherent contradiction perplexed the SDF personnel in the field, thereby raising a necessity for law amendment (see Chap. 3). Another restriction was imposed on SDF peacekeepers regarding the use of weapons. The concrete details of weapons carried were not mentioned in the law. Instead, these would be determined by the Diet on a case-by-case basis, as a part of the inevitable process of drafting the “Implementation Plan” that would define the details for the deployment (see Chap. 2). When the dispatch to Cambodia was decided, the Diet permitted SDF personnel to carry only light weapons, such as sidearms and automatic rifles (Cabinet Office, 1992). This measure was taken to reduce the risk of involving the SDF in direct fighting, but it seemed doubtful that the arms permitted would be sufficient to protect troops when the Khmer Rouge was equipped with heavy weapons, including rocket artilleries, mortars, and tanks.

The first military contribution to the UNPKO was a huge political challenge for the Miyazawa government. To avoid criticism from the anti-military camp, the government was very cautious that the deployment to Cambodia would be compatible with Japanese legal requirements. The question of compliance with the Five Principles in particular was so concerning that Miyazawa repeatedly stressed the importance of taking an extremely careful stance toward Cambodia, in light of the fact that it was Japan’s first participation in a UNPKO (“Tesaguri no PKO shita-shirabe,” 1992). Moreover, with the “freeze” on the PKF’s main duties (see Chap. 2), the GoJ was unable to send an infantry force and instead placed the JEG as the centerpiece of the Japanese delegation (Kuriyama, 2016, p. 194).

Albeit under these restrictions, the GoJ was highly motivated to marshal their best possible efforts in their UNPKO debut. The Implementation Plan for Cambodia expressed the GoJ’s willingness to respond as much as possible to all UN requests and “to proactively make the largest possible personnel contribution” (Cabinet Office, 1992). As a result, the GoJ decided to dispatch a large-scale delegation composed of more than 700 peacekeepers, including not only military personnel but also civilian members, to UNTAC. The delegation consisted of 600 engineering forces, eight unarmed military observers, 75 civilian police officers, and 41 civilian election observers (Cabinet Office, 1993).Footnote 1 The engineering unit represented the largest element of the Japanese peacekeeping team.

5 Overview of Japan’s Activity in UNTAC

5.1 The JEG’s Activities in Civil Affairs Support

The largest part of the Japanese delegation (i.e., the JEG, the unarmed military observers, and the civilian police officers) arrived in Cambodia between September and October 1992, while the electoral observers were scheduled to arrive the following spring, immediately before the general election. At that time, UNTAC’s military section upheld a policy of providing safety and support to election observers (Murakami, 2017). All engineering units that contributed to UNTAC were ordered to provide surveillance and logistics assistance to support the upcoming general election, while also urgently repairing infrastructure. The Japanese side curtly declined to do so, however (Ground Staff Office, 1995a, p. 226).

The reason for this was twofold: First, security-related tasks, or “PKF main duties” to use the Japanese term, were “frozen” in the PKO Act at that time (see Chap. 2). Second, the Implementation Plan allocated the engineering unit only to construction and other logistic works, such as transportation and storage. Election assistance was not included as a part of their formal role. For these reasons, the GoJ insisted to UNTAC that it was impossible to task the JEG with electoral assistance, especially if this was a security-related duty. The justification based on the Japanese legal constraints inevitably displeased the UNTAC side, but the JEG initially stuck to civilian engineering duties.

At the outset and as planned, the JEG focused on the repair of main supply roads and bridges in Takeo. Most notably, the JEG rebuilt National Highway Routes 2 and 3, which were the main trunk lines in the region. The road repair not only facilitated UNTAC activities but also improved transportation to help the local people to travel to their polling stations for the upcoming election. Contributed as a part of the UN framework, the JEG was theoretically supposed to work for UNTAC, but they aimed to build a close relationship with the local population (Oyama & Akiho, 2020, p. 108).

For these purposes, the JEG planned to engage in civil affairs support, or direct assistance to the residents, which they called “another PKO” (“Kokusai-koken eno tabidachi,” 1992). In sum, the Japanese side regarded the engineering activity more as reconstruction assistance to the local society rather than logistic support for peacekeeping (Honda, 2017). Put another way, the JEG’s work took on characteristics closer to peacebuilding during their first deployment to the UNPKOs. As intended, JEG members successfully developed friendly relationships with local people, going shopping and sightseeing together, for example, or being invited for meals (Oyama & Akiho, 2020, p. 110). On leaving Cambodia a year later, moreover, the JEG “presented” their used materials to the locals (“Jiei-tai ga tesshu e,” 1993). Although their true intention was reportedly to reduce the burden of transporting them back to Japan, the Cambodian side highly appreciated their donations, including prefabricated accommodation, medical materials, and dynamos (“Jiei-tai no takeo-shukuei-chi,” 1993). These successful experiences in civil affairs support would later develop into the “All Japan” approach (Uesugi et al., 2016).

5.2 The Expansion of JEG Duties Without a Formal Mandate

When the Japanese contingent started their activities in autumn 1992, meanwhile, the Khmer Rouge was further escalating security concerns. Earlier, in June of that year, they declared that they would abrogate the agreement of disarmament. In October, they also proclaimed that they would boycott the general election and blew up two bridges crossing over a main roadway in the Central Kampong Thom Province. Later in the same month, bombardment was exchanged between the Khmer Rouge and the Cambodian government’s forces in the same province. The extremists also launched rocket guns against a residential area near the capital city. In the following month, the Khmer Rouge threatened to attack UNTAC. It was now obvious that the Asian nation was deeply embroiled in violent instability, but the GoJ kept denying that the cease-fire agreement had already been lost.

Meanwhile, UNTAC asked the GoJ to assign the JEG additional logistics roles, such as water supply and refueling for UNTAC contingents. Although not mentioned in the original plan, the GoJ endorsed the SDF’s new tasks in December 1992. In early 1993, UNTAC again requested that the GoJ assign more responsibilities to the JEG. In response to this, in February 1993, the GoJ additionally assigned the medical assistance role to the JEG. The GoJ also expanded the geographical range of their construction work. This endorsement was possible because the additional duties were not related to the PKF’s main duties and were allowed under the existing Implementation Plan. In this way, the JEG gradually took on greater roles to cope with the reality on the ground, while still shying away from election assistance. In March 1993, the second engineering team arrived in Cambodia on rotation. By that time, the local situation had become even more tense, as the general election in May of that year was drawing near. Nevertheless, the GoJ still insisted that the cease-fire agreement was being maintained.

5.3 The Loss of Japanese Personnel in a Tough Security Environment

Under such unstable circumstances, two Japanese personnel lost their lives to alleged assaults by the Khmer Rouge. On April 8, a young UN volunteer, Atsuhito Nakata, was shot dead in the Kampong Thom Province. Although he was not part of the Japanese national delegation, his violent death was a great shock for Japan. This tragic event inevitably increased vigilance on the Japanese side. Later that month, the GoJ demanded that UNTAC enhance security measures to protect Japanese civilian police officers.

Despite these efforts, another tragic incident occurred on May 4. A team of five Japanese civilian police officers were assaulted near a village called Ampil, located on the northwest edge of Cambodia, while they were patrolling the neighborhood (Hatate, 2018). Although they were being escorted by the Dutch infantry unit, one of the Japanese policemen, Inspector Haruyuki Takata (promoted to superintendent after his death), was killed by gunfire. The Khmer Rouge was assumed to be responsible for his murder. This horrific event shook the Japanese government and society. Since the decision was taken to contribute to UNTAC, Japanese eyes had been mostly on the JEG at the expense of other components of the Japanese delegation, such as the police. Having received the tragic news, Chief Cabinet Secretary Yohei Kono frankly admitted: “We [the GoJ] focused only on the SDF and were not concerned enough about the civilian police officers” (NHK-supesharu, 2016).

In fact, Japanese civilian police officers were facing a much more challenging situation in Cambodia than the JEG, who were at least armed (albeit only with light weapons) and acted as a large-scale unit. From October 1992, a total of 75 Japanese civilian police officers were deployed to 29 locations all over Cambodia. They assumed the responsibility of advising and supervising the Cambodian police force. Unlike the JEG, located in the relatively stable Takeo, the civilian police personnel were deployed to different locales and environments, including highly dangerous areas under heavy Khmer Rouge influence. Ampil was one of these danger zones. Moreover, following the general custom of UN civilian police, the Japanese police were unarmed while on duty and usually worked in small teams. Japanese civilian police officers were often perplexed by UNTAC’s excessive requests beyond the official mandates, particularly in rural areas such as Ampil, where the local police often did not function as expected or were virtually nonexistent. In such cases, it was necessary for the UN civilian police to compensate for the incompetence of the local police by engaging in dangerous tasks, such as patrols, without a formal mandate. These concerns culminated in the death of the civilian police officer. Fortunately, there were no more fatalities after Takata, but the killing of a civilian police officer highlighted the stark danger of participation in UNPKOs.

The tragic death of the civilian policeman necessarily raised concerns that the cease-fire had already collapsed, putting huge pressure on the GoJ to bring the entire Japanese delegation home. However, the GoJ never admitted the violation of the truce despite having faced such an emergency. Instead, the GoJ resolutely declined the idea of withdrawal from UNTAC, insisting that the Five Principles remained intact. Because the deployment to UNTAC was the first memorable milestone in Japan’s peacekeeping policy, the GoJ was determined to accomplish it in spite of a seriously unstable local situation. As Prime Minister Miyazawa stated, “Let us hang in there to complete the half-finished job” (Takeuchi, 1994). With such an adamant political resolution, the gap between official legal assumptions and the brutal reality on the ground grew ever larger.

5.4 The Assignment of de facto Security Duty to the JEG

With increasing insecurity on site, the JEG was eventually assigned to electoral assistance duties in April 1993 to meet UNTAC demands in preparation for the upcoming election the following month. Although the Implementation Plan did not technically authorize electoral assistance, the GoJ opted for a flexible interpretation of the Plan and decided to assign them this duty. The JEG consequently assumed a variety of electoral support tasks, ranging from transportation and storage of foodstuffs to the construction of voting stations. Entering into the election-related mission under UNTAC now exposed the JEG to a greater threat of Khmer Rouge attack. Meanwhile, Japanese electoral observers were scheduled to arrive shortly thereafter, raising an acute question of how to protect them.

To cope with this pressing situation, the GoJ decided to assign the de facto security-related mission to the JEG. On May 13, the GoJ declared that it would assign the engineering forces to engage in “patrol” duty in areas where Japanese electoral observers would be deployed. This immediately invited criticism because “patrol in a buffer zone” was part of the “frozen” PKF main duties. No matter how the GoJ tried to justify this decision, it appeared to be a patrol in practical terms. The anti-military opposition camp sharply derided this as a haphazard decision, but the government remained determined to task the JEG with protecting the electoral observers, even if this virtually broke the prohibition on security-related tasks. Prime Minister Miyazawa maintained that the mission would be considered as “information gathering” for the construction works that constituted the JEG’s formal mandate (“Kambojia deno Jiei-tai,” 1993). However, it seemed obvious that the government’s real intention was to use the armed engineering unit to protect the unarmed electoral observation unit.

5.5 The JEG’s Provision of Security for Japanese Electoral Observers

On May 17, a few days before the prime minister’s remarks, the Japanese electoral observers arrived in Cambodia as scheduled. The team comprised 41 civilian personnel and was assigned to monitor voting and counting of ballots. All team members were deployed to various counties in the Takeo Province, with one being allocated to each polling station to supervise voting and counting. With the election fast approaching, security concerns were rising around the country and even in Takeo, which was perceived a relatively safe city in comparison with the other places under the Khmer Rouge’s strong influence.

On May 21, the JEG escorted observers to their polling stations and also visited them regularly to bring food and water. By carrying rifles, the JEG essentially embarked on a security mission, albeit in the name of “information gathering.” The JEG also engaged in other electoral support duties, such as delivering materials and meals. One of the observers expressed a feeling of relief, saying, “The SDF’s presence makes us feel safer” (“Ho-jin-senkyo-kanshi-in,” 1993). Other members of the electoral team, however, were more critical about the SDF’s de facto patrol, with one stating, “We only saw them for at most five minutes in the daytime. The most dangerous time of day for us was at night, so we asked them to come at night if they were going to make an ‘actual patrol’” (Shinoda, 1994, p. 259). This critical comment cast doubt as to whether their de facto patrol was actually useful in improving the safety of electoral observers. In other words, the SDF’s de facto patrol raised questions not only concerning its legal legitimacy, but also in terms of its actual performance.

More seriously, the security provision for the electoral observers highlighted the delicate problem of the strict constraints on the use of weapons in the original PKO Act. The use of weapons by SDF peacekeepers was permitted only for self-preservation. This constraint excluded the possibility of protecting civilians in distant places, except in rare cases where an urgent danger also directly threatened SDF personnel (see Chap. 3). Realistically, it would be difficult for armed SDF personnel to overlook a call for rescue by non-armed personnel. Exploiting a legal loophole, the Ground Staff Office ordered JEG peacekeepers in Cambodia to prepare to risk diving into a dangerous situation to gain closer proximity to civilians, just to then be able to legally use their weapons in the name of self-preservation, even though this never happened in practice (Ground Staff Office, 1995b, p. 87). This is the origin of the “coming-to-aid” duty problem (see Chaps. 3 and 4). Fortunately, such a situation was improbable in practice, but the question remained unresolved. A similar issue reemerged later during Japanese peacekeeping participation in the former Zaire and East Timor (see Chaps. 3, 4, and 6).

The election was due to begin on May 23, 1993, and continue until May 28 of the same year. As these dates approached, tension and vigilance mounted. The GoJ became increasingly nervous about not only the safety of civilian personnel but also of the JEG. On May 22, 1993, the day before the first vote was cast, the JEG were additionally tasked with the transportation of ballot boxes, which could be highly dangerous because the Khmer Rouge might attempt to despoil them.

In the end, the general election was held successfully all over Cambodia. The turnout rate was very high, exceeding 70–80 percent in most provinces and sometimes even surpassing 90 percent (“Kambojia-so-senkyo,” 1993). There were some armed attacks against UNTAC forces but no fatalities. The delivery and counting of votes were also carried out without serious trouble. Prince Sihanouk’s party won the election. In September 1993, a new constitution was promulgated, and the Kingdom of Cambodia was reconstructed, thereby terminating the operation of UNTAC. In light of this accomplishment, UNTAC operations were generally regarded as a success despite the loss of more than 70 UN personnel.

6 Japan’s Efforts in Cambodia and Its Challenges

6.1 Gaps in the Existing Legal Structure

As novice peacekeepers, the Japanese delegation in Cambodia discovered numerous problems through firsthand experience on the ground. One of the most significant was the gap between theoretical legal assumptions and the empirical reality in Cambodia, especially local insecurity. These fissures were seen at two levels: the gap between officially assigned tasks and the practical roles imposed while on the job without a legal basis, and the gap between the official judgment on the operational environment and the reality of local instability.

Japanese civilian police officers encountered the first serious gap between the official duties and the practical roles given in the field. As seen earlier, the UN civilian police personnel were only supposed to work unarmed to advise and supervise the local police forces, on the assumption that the local police already functioned properly. Nonetheless, local policing capacity was virtually nonexistent, especially in rural areas, and the Japanese civilian police had to engage in de facto policing duties, such as patrolling. A quarter of a century later, it was shockingly revealed that in this tense situation, some Japanese police officers had personally purchased automatic AK-47 rifles (Hatate, 2018). Needless to say, this was in violation of the PKO Act, but circumstances were fraught with tension and it was too dangerous for them to work unarmed.

Second, the gap between the official assessment of the operational environment and the reality of local insecurity also grew more salient. The GoJ decided on the dispatch to Cambodia on the grounds that the cease-fire agreement was made at the Paris Peace Agreement in 1991. In practice, the Khmer Rouge soon dropped out of the agreement and much of Cambodia had already reverted to a de facto civil war situation when the Japanese delegation arrived there. Yet, the GoJ firmly upheld its position that the cease-fire was maintained because if the truce had been broken, then the Five Principles demanded the Japanese delegation’s immediate withdrawal. For the GoJ, it was out of the question to withdraw from this flagship enterprise, which was intended to represent Japan’s first military contribution under the political goal of “International Contribution.” Underneath this political determination, the gap between peacekeeping law and practice continued to grow.

6.2 Altered SDF Roles to Protect Japanese Nationals in the Field

In increasing insecurity, the JEG unexpectedly had to assume a de facto security role to provide protection to the Japanese civilian electoral observers. This entailed a huge problem both legally and practically. In light of legal legitimacy, it was highly problematic for the SDF to assume a new task without a legal basis. It was particularly so not only because the addition of the de facto security task lacked a formal mandate, but also because such a duty was suspended under the Japanese legal system.

Related to these points, there was a more intricate problem regarding the permitted range for the use of weapons. Under the original PKO Act, SDF peacekeepers were allowed to use weapons exclusively for self-preservation (see Chaps. 3 and 4). Under this rule, the engineering unit would not be allowed to fire to protect civilians even if they were located in the same place as the SDF personnel. Fortunately, the SDF personnel on the de facto patrol duty never encountered this situation, but it left a serious future agenda as to whether the GoJ should relax the constraint on the use of weapons specifically for the protection of civilians. Awareness of this issue would lead to the addition of the so-called “coming-to-aid” duty in the amended PKO Act in 2015, after 22 years (see Chap. 4).

6.3 Other Outcomes and Lessons Learned

Among the various works carried out by the Japanese delegation to UNTAC, the engineering forces left the most visible achievements. By the end, they had built approximately 100 kilometers of roads and paved 10 kilometers, and also repaired 40 bridges. This opened up routes for the return of more than 300,000 refugees, enabling them to participate in the 1993 elections. Further, more than 800 tons of water were supplied to UNTAC personnel, along with 8000 kiloliters of fuel and approximately 1000 medical cases for first aid (Ground Staff Office, 1995a, p. 173). When social infrastructure had been seriously damaged due to the civil war, the JEG’s support made a considerable contribution to facilitating UNTAC activities while also leaving a positive impact on the local society. Later, Japan’s ODA continued to provide infrastructure development support to Cambodia, exemplified by the restoration of National Highway Route 1.

From this experience, the GoJ realized that JEG-focused deployments to a UNPKO would provoke little political controversy (Cabinet Office, 1997). The JEG also established a friendly relationship with the locals in Takeo. For example, a study by Oyama and Akiho (2020), which is based on their field research, testifies that locals and SDF personnel exchanged gifts as farewell tokens when the Japanese troops were about to leave.

In the meantime, the Japanese delegation also understood the importance of deploying staff officers to local UN mission headquarters on site for the purpose of information gathering, for coordination among concerned parties, and for the delivery of their own requests to the UN (Honda, 2018). While in Cambodia, SDF peacekeepers saw that UN headquarters personnel from other countries prioritized their own countries’ troops when assigning work. The JEG could not expect such favorable treatment, having no Japanese staff assigned to the headquarters. Having learned from this lesson, the GoJ would dispatch staff officers in subsequent deployments to the later UNPKOs in Mozambique, the Golan Heights, East Timor, and South Sudan.

6.4 Summary of Chap. 5

Before the SDF’s deployment to Cambodia, Japanese government and peacekeepers had been primarily preoccupied with the observance of the PKO Act. Once dispatched, Japanese personnel, especially the JEG and civilian police officers, soon faced the bitter truth that UNPKOs differed in practice from the theoretical assumptions made by the Japanese legal system. This gap made it very hard for them to adhere to the legal mandates and stipulations in the PKO Act. The belittlement of the law was attributed to both the UN side and the GoJ. On the one hand, the UN side repeatedly demanded expansion of the range of activities for Japanese personnel, even without a formal mandate to do so. On the other hand, the GoJ had never admitted the collapse of the cease-fire and maintained the presence of Japanese peacekeepers on site despite the mounting danger on the ground. In light of the grim local reality in Cambodia and repeated requests from the UN, Japanese peacekeepers, especially the JEG and the civilian police officers, were gradually assigned more demanding roles, despite the GoJ’s initial declaration of support for caution and adherence to the law.