The 12.3 Martial Law Incident and Challenges in South Korea’s Civil–Military Relations

Jungsup Kim

Principal Research Fellow, Sejong Institute

Summary

1. Issue Overview

The 12.3 Martial Law incident was a stark reminder of the nightmare of military coups, once thought to be a relic of the past, through the mobilization of the armed forces, which are supposed to defend national security and constitutional order. Unlike a conventional military coup in which the military unilaterally overthrows the civilian government, this case was orchestrated and initiated by the president at the apex of the command structure. The soldiers deployed to the National Assembly, many without knowledge of the broader plan, could be seen as victims themselves. In fact, signs of passive resistance and discomfort with their mission were observed during the incident.

While the military may not bear full responsibility for the martial law crisis, the ease with which military force was mobilized at the president’s command exposes a structural vulnerability in South Korea’s civil–military relations. It serves as a wake-up call to reassess how democratic society should manage and oversee its armed forces. This is inherently a complex issue: society must satisfy two often conflicting imperatives, defending against external threats and safeguarding internal democratic order.

The paradox at the core of civil–military relations is this: the military exists to protect society, but it also possesses the potential to threaten it. If the focus is placed excessively on external threats and the military is granted unlimited autonomy, the state risks losing control over its armed forces. Conversely, if civilian oversight becomes overly restrictive, the military may become too weakened to effectively respond to real external dangers. The challenge, therefore, lies in striking the right balance: ensuring the military has the capacity to fulfill its core defense mission while maintaining robust democratic control over its actions. Society entrusts the military with the mission of protection but must retain a corresponding responsibility for legitimate command and supervision.

2. The Concept and Theoretical Foundations of Civilian Control

Civilian control refers to the democratic principle that decision-making authority over national defense policy should be held not by professional soldiers but by civilian political leaders. Democratic principles must be applied without exception to military affairs as well, because civil–military relations are merely a particular form of the delegation of popular sovereignty that underpins the functioning of any democratic state.

Alongside democratic theory, civilian control is also necessary for practical reasons: when the military is not properly controlled, it can influence society in unintended ways. There is no such thing as a purely military issue—decisions about the size of the military, defense budgets, length of service, or military strategy all have profound effects on society. For example, the size of the defense budget reflects national priorities, and the duration of mandatory service affects young people's entry into the workforce and national competitiveness. At the same time, it is essential that civilian oversight does not undermine the military’s primary mission of protecting society from external threats. Based on this awareness, various theories of civilian control have been developed over time.

1) Principal–Agent Model

The principal–agent model views civil–military relations as a type of contractual relationship, similar to many aspects of social life. When a person is ill, they entrust treatment to a doctor (the agent) with professional expertise, or when a car breaks down, the owner commissions a mechanic to handle repairs. The problem arises when there is a difference in priorities between the principal and the agent. For instance, a doctor and a patient may disagree on treatment costs, risks, or alternative options, or a mechanic may recommend unnecessary parts replacements.

Civilians and the military share the common objective of securing national defense. However, disagreements arise over how to pursue that goal and how much should be invested. Typically, the military prefers the use of overwhelming force and offensive doctrines. This stems from its desire to minimize the risk of defeat in an unpredictable war and to maintain maximum operational autonomy. The military also tends to exaggerate threats, due to its institutional nature of thinking about and training for war on a constant basis. These preferences may not always align with societal expectations.

As a result, society must retain a certain degree of control over the military’s preparation for and conduct of war. This brings attention to the challenge of balancing delegation and monitoring. Authority should be delegated to the military to some extent due to its professional expertise, but civilian leadership must not relinquish its capacity or legitimacy to supervise military actions.

One key issue in finding this balance is the problem of shirking, which arises from the information asymmetry between principal and agent. While civilians are the principals, the military, as the agent, possesses far superior knowledge and exclusive information. This allows the military to potentially distort or shape situations according to its own preferences. For example, the military may exaggerate the risks or costs associated with a civilian-preferred policy, downplay the benefits of organizational integration, or warn against the dangers of shortening military service periods.

There are cases where the military may limit available policy options altogether. After the Vietnam War, the U.S. Army institutionalized the lesson that war should not be fought without full public support. It reorganized its force structure to rely heavily on reservists, thereby making it impossible to engage in a major war without their mobilization. The military may also protect its own interests by withholding information, exploiting political divisions, or deliberately delaying implementation of policies it opposes.

If shirking represents deviant behavior on the part of the agent (the military), civilian leaders must also guard against the risk of adverse selection. The military is an institution meant to fight, and it requires a proper military mindset. Excessive civilian control may result in the over-projection of civilian values into the military, potentially leading to the civilianization of the armed forces. This, in turn, could create conditions in which officers who are more compliant with civilian authority are favored for promotion, thereby triggering adverse selection in the cultivation and appointment of key military leadership.

2) Huntington’s Professionalism and Cohen’s Unequal Dialogue

In his landmark work The Soldier and the State, Samuel Huntington proposed a model of civil–military relations based on military professionalism and objective civilian control. He viewed the military as a professional body, akin to lawyers or doctors, that provides essential services for the functioning of society. According to Huntington, objective civilian control refers to a form of civil–military relations in which civilian leaders refrain from intervening in the military’s core areas of expertise and autonomy. By respecting this boundary, the military is more likely to voluntarily submit to civilian authority, thereby preserving its political neutrality and maximizing its operational effectiveness. In contrast, subjective civilian control entails direct interference by civilians in military affairs without regard for the military’s unique domain or expertise. This approach risks undermining the military’s professionalism and efficiency, and may lead to the imposition of liberal civilian values that are incompatible with the nature of military institutions.

However, Huntington’s concept of objective civilian control has drawn significant criticism. First, it potentially clashes with core democratic principles, as it implies the existence of a policy domain beyond the reach of civilian or public oversight. Second, the clear-cut separation of roles between civilians and the military does not reflect the practical reality in which the two domains often overlap. Third, the notion of military expertise itself is subject to doubt; in many countries, the military lacks actual combat experience, which raises questions about whether the expertise gap between civilians and soldiers is sufficient to justify exclusive control by the military.

Responding to these criticisms, Eliot Cohen has offered an alternative perspective: the ideal model of civil–military relations is not based on excluding civilian involvement in military affairs, but on fostering close and continuous dialogue between civilian and military leaders. Drawing on examples of wartime leadership by figures such as Lincoln, Clemenceau, and Churchill, Cohen highlights how these leaders were deeply involved in military decision-making, contrary to Huntington’s recommendations. On this basis, he introduces the concept of an unequal dialogue as the normative ideal for civil–military relations.

According to Cohen, the focus should not be on rigid role separation or unidirectional orders and obedience, but on sustained, substantive exchanges between the two sides. However, because the ultimate authority for decision-making must rest with civilian leaders, this dialogue is inherently unequal. From this perspective, the key to building sound civil–military relations lies not in expanding military autonomy grounded in professionalism, but in cultivating capable and well-prepared civilian leadership that can engage in and guide these critical conversations.

3) Institutionalism: The Roles of the Legislature and the Ministry of National Defense

Institutions refer to the formal and informal rules, procedures, and cultures that guide and regulate behavior within organizations. They shape patterns of interaction and identity among individuals and organizations, and play a key role in defining power relationships. The institutionalist approach applies this logic to civil–military relations, asserting that they too can and should be structured and regulated through institutional mechanisms.

In democratic societies, the legislature is a core institution and plays a major role in shaping civil–military relations. First, through its legislative authority over defense matters, the legislature reflects the public’s perspective and applies pressure for change in defense policy. Second, its authority over budget planning and execution enables the legislature to influence resource allocation and military operations. Third, its oversight functions—such as committees, audits, investigations, and hearings—allow it to monitor the military in response to public concerns. However, civilian control through legislative means also faces limitations, such as a lack of defense expertise, partisan interests, and constraints tied to committee structures.

The most critical mechanism for ensuring routine civilian control is the Ministry of National Defense (MND), which connects elected civilian leadership with the military. Without the MND, democratic oversight of military affairs would be nearly impossible. To establish security strategy, coordinate with other state agencies, manage resources, and regulate inter-service competition, a centralized organizational structure is essential.

The Ministry of National Defense fulfills multiple key roles. First, it defines the power relationship between the military and the civilian government. The existence of the MND and the fact that the armed forces are managed by a civilian minister means the military is institutionally subordinated to the executive branch. Second, the MND sets the boundaries of military authority and civilian responsibility by defining the military’s scope of influence in budgeting, force structure, capability enhancement, and strategy. Third, it functions as a communication channel between civilian and military actors; the civilian defense minister often serves as a spokesperson for military perspectives in external forums. Fourth, the MND is essential for ensuring the effective use of resources, requiring a management mindset capable of overseeing large-scale organizational and financial operations. Finally, the ministry is responsible for integrating and coordinating the branches of the armed forces to maximize jointness and overall defense capability.

3. Assessing Civil–Military Relations in South Korea

The major theories of civilian control discussed above provide a useful framework for evaluating the health and stability of civil–military relations in South Korea. Is there an appropriate balance between delegation and monitoring? Are there effective civilian control mechanisms in place to overcome the disadvantages of information asymmetry? (Principal–Agent Model) Is objective civilian control functioning in a way that respects military professionalism and efficiency while ensuring political neutrality? Or is subjective civilian control evident, with excessive civilian interference undermining military effectiveness and leading to politicization? (Huntington’s Professionalism) Are civilian leaders adequately trained and prepared to engage in deep, meaningful dialogue with the military on defense matters? Or do rigid role boundaries persist, creating barriers and tensions in civil–military interaction? (Cohen’s Unequal Dialogue) Are the National Assembly and the Ministry of National Defense fulfilling their institutional roles? Is the legislature effectively reflecting public opinion in defense policy and military operations through its legislative, budgetary, and oversight functions? Is the Ministry of National Defense, as the key link between elected civilian leadership and the military, effectively guiding, controlling, and representing the military while playing a central role in shaping national defense policy? (Institutionalism)

1) Domination of the Military Elite by Service Academy Graduates

South Korea has a diverse officer commissioning system, including the military academies, ROTC (Reserve Officers' Training Corps), OCS (Officer Candidate School), and the Korea Army Academy at Yeongcheon (KAAY). Despite this diversity, graduates of the service academies account for only about 10% of newly commissioned officers, a relatively small share. However, as officers rise through the ranks, this ratio reverses—service academy graduates become increasingly dominant in higher ranks. At the company-grade level, their share is only 12–14%, but this rises to 41–44% at the field-grade level, and among general officers, they comprise over 80%, leaving less than 20% combined for ROTC, OCS, and KAAY graduates.

The reason service academy graduates, though a minority at the time of commissioning, come to dominate the upper ranks lies in the differentiated career tracks embedded in the personnel system. Under current military personnel laws, service academy graduates are expected to serve long-term by default, which allows them relatively smooth promotion at least to the rank of lieutenant colonel (with a 89% promotion rate from major to lieutenant colonel), and makes advancement to colonel or general more accessible. In contrast, non-academy officers are initially recruited for short-term service. Even if they choose to pursue a military career, they must pass a selective screening process for long-term retention, creating a structural barrier from the outset.

Even after long-term selection, significant disparities in promotion rates persist depending on commissioning source, and the share of non-academy officers drops sharply at higher ranks. The promotion rate from captain to major is 98% for academy graduates, compared to 75% for non-academy officers. From major to lieutenant colonel, the rates are 89% and 48%, respectively. The disparity widens at higher levels, with colonel promotion rates at 59% for academy graduates versus 22% for others. From colonel to brigadier general, the rates are 31% and 18%, respectively. These differences may partly reflect individual performance, but the current personnel management system and the resulting structural disparity in career advancement discourage talented individuals from joining the ROTC and OCS pipelines. The fact that a particular school background monopolizes the upper command of the armed forces poses a challenge to both democracy and military development. It is therefore necessary to reconsider personnel policies to ensure greater balance. In South Korea’s unique culture of school and class-based networks, the dominance of a single background like the military academy can foster strong internal networks, which in extreme cases may prioritize personal connections over public values.

2) Politicization of Military Personnel Appointments

The president’s authority over military personnel appointments is entirely consistent with democratic principles, and in fact represents one of the most effective means by which elected civilians exercise control over the military. However, excessive political interference in personnel decisions risks undermining the military’s autonomy and deepening its political subordination. For this reason, the exercise of appointment authority must be conducted with appropriate restraint and procedural integrity. In principle, the promotion of general officers follows the formal process of recommendations by the Chief of Staff of each service, endorsement by the Minister of National Defense, and final approval by the president.

In practice, however, the presidential office is known to intervene from the earliest stage under the justification of prior vetting, often playing a decisive role in shaping the initial personnel proposal. When each service submits its candidate data, the presidential office frequently drafts the personnel outline and then relays it back to the respective Chief of Staff—a pattern that has become increasingly common in recent general officer appointments. Political considerations such as preference for individuals loyal to the current administration, exclusion of figures associated with previous governments, and the potential influence of personnel lobbying are often taken into account. These practices reflect what Huntington characterized as a form of subjective civilian control, where excessive political involvement in military affairs undermines merit-based appointments and, ultimately, weakens combat effectiveness. Moreover, such dynamics may foster a culture of favoritism between political leaders and senior officers, raising the risk of loyalty-based mobilization, including potential complicity in a praetorian coup.

3) Institutional Foundations of Civil–Military Relations: The Ministry of National Defense and the National Assembly

As a mechanism linking elected civilian leaders and the military, the Ministry of National Defense (MND) serves as a core institutional foundation of democracy by pursuing both military readiness and civilian control. While the role and status of the MND have improved over time, several shortcomings remain. Most notably, since the Park Chung-hee administration, no civilian has been appointed as Minister of National Defense; the position has consistently been held by retired generals. Given that the MND was established to bring the military under cabinet-level civilian control, appointing former military officers to lead the ministry undermines its original purpose. Paradoxically, the presence of a retired general at the top of the ministry has also contributed to diminishing the authority and role of the Chairman of the Joint Chiefs of Staff and the service chiefs.

Another structural issue is the low ranking of the Vice Minister of National Defense within the military hierarchy, where the position is considered equivalent to the ninth highest-ranking officer. Since the vice minister is ranked below field commanders, there is a widespread perception within the military that the vice minister is equivalent to a three-star general. While formal precedence does not always directly impact authority in peacetime, the problem becomes more apparent when the vice minister must serve as acting minister. In such cases, the vice minister is expected to oversee both administrative and operational command functions, including coordination with the Joint Chiefs of Staff and service headquarters. However, due to the perception that the role is junior in status, resistance from within the military may arise.

Although the civilian composition of the MND headquarters has reached over 70% on paper, many key positions are still held by retired military officers rather than career civil servants. As a result, the MND is often criticized for being “civilianized in appearance only.” In particular, critical posts are still largely occupied by active-duty officers—especially those from the Army—giving rise to the derogatory term “Yookbangbu” (literally, "Army Ministry"), which reflects the perception that the ministry functions more as a command echelon above the Army and service headquarters than as a central government agency.

The National Assembly contributes to democratic oversight of the military through its powers over budget, legislation, hearings, and audits. However, its role in areas such as personnel appointments and force structure control remains limited. Unlike the U.S. Congress, which holds confirmation hearings for a wide range of top military positions including the Chairman of the Joint Chiefs, service chiefs, and major field commanders, the South Korean National Assembly only holds hearings for the Chairman of the Joint Chiefs of Staff. Furthermore, although the legislature has authority over defense budgeting, it currently lacks an effective system for overseeing or regulating military end strength.

4) Officer Training System and Military Culture

To prevent unconstitutional acts of insurrection, it is essential to establish a military culture and identity grounded in loyalty to the Constitution and the people. In the South Korean military, however, there exists a tradition of absolute obedience to superiors and a culture of excessive loyalty. Such norms within the upper echelons of the armed forces are closely tied to the lack of institutional safeguards for personnel stability. It has become customary for large-scale changes in promotions and appointments of senior generals to occur whenever a new administration takes office.

The military academy system, which is responsible for training junior officers, also requires review in terms of cultivating democratic values and a constitutional military identity. Military academies play a central role in producing elite officers and internalizing the core identity and values of the armed forces. At the same time, these academies also serve as public institutions that confer academic degrees, and should therefore help cadets develop civic literacy by offering education in disciplines such as law and economics in addition to military science. The problem, however, is that the teaching staff at the academies is overwhelmingly composed of active-duty officers, mostly alumni of the same institutions, with civilian professors making up only slightly over 10% of the faculty.

4. Establishing Sound Civil–Military Relations

1) Institutional and Structural Reforms: Strengthening the Roles of the Ministry of National Defense and the National Assembly

The foundation of proper civilian control begins with a system in which the military is directed and supervised by a civilian Minister of National Defense. With the exception of socialist and authoritarian states, nearly all democracies around the world manage their militaries through civilian defense ministers. The appointment of a civilian minister is expected to bring about a healthier division of roles between the Minister of National Defense, the Chairman of the Joint Chiefs of Staff, and the service chiefs. In such a structure, the minister would focus more on setting policy and strategic direction, while military authorities would have greater autonomy in operational matters and unit-level management.

To ensure that the Ministry of National Defense functions as a stable foundation of routine civilian control in a democratic system, its institutional authority must be redefined. The ranking of the Vice Minister should be elevated from its current position as ninth in the military hierarchy to second, thereby clearly establishing the vice minister as the military’s senior civilian official. This change is not merely a matter of protocol but a reflection of the principle that the military must remain under civilian cabinet-level control. To support the civilian defense minister, the role of career civilian officials within the ministry must also be expanded. A phased civilianization of key positions—particularly in policy, force development, and personnel—should be pursued.

The National Assembly, beyond its current roles in legislation, budgeting, and oversight, should expand its institutional functions. These include widening the scope of confirmation hearings for senior military appointments, establishing mechanisms for monitoring and regulating military end strength, and taking on a more active role in reviewing military strategy and force enhancement plans.

2) Reforming Military Personnel and Appointment Policies

To mitigate the dominance of service academy graduates within the upper ranks of the armed forces, a more balanced approach to personnel and appointment policies is needed. Fundamentally, the purpose of utilizing human resources in the military should be standardized toward long-term service, regardless of commissioning source. This would help eliminate structural disparities in career stability between academy and non-academy officers.

To address the negative effects of subjective civilian control and prevent the politicization of the military, the general officer appointment system must be reformed. Early-stage intervention by the presidential office, as is currently the norm, fosters an unhealthy entanglement between political power and the military, posing risks to democracy and constitutional order. Moving forward, the personnel process should adhere to the proper sequence: recommendation by the service chief, nomination by the Minister of National Defense, and final vetting by the presidential office. While some level of presidential and ministerial involvement is inevitable for promotions at the lieutenant general level and above, appointments from colonel to brigadier general should primarily reflect the judgment of the respective military branches, with political considerations limited to setting general policy direction and verifying candidate suitability.

For positions where terms are defined by law—such as the Chairman of the Joint Chiefs of Staff, the service chiefs, and the Commandant of the Marine Corps—tenure should be respected barring extraordinary circumstances. This would help foster an institutional culture where senior officers can carry out their duties with professionalism and independence.

3) Establishing Military Identity and Reforming Officer Training Systems

It is essential to establish a military identity grounded in the concept of “uniformed democratic citizens.” No institutional mechanism can fully guarantee the political neutrality of the armed forces; rather, the key lies in restoring a proper sense of military professionalism through joint efforts between civilian and military actors. Like in Germany, military identity should not be based on blind obedience or excessive loyalty to superiors, but rather on allegiance to liberal democracy and the Constitution. This principle must serve as the foundation of military education and organizational culture. In this regard, reforming the military academy system—which has a profound influence on the values of young junior officers—is critical. Civilian professors should make up at least 50% of the faculty to ensure that the academies provide not only technical military training, but also rigorous higher education and civic education that nurtures democratic citizenship.

4) Strengthening the Societal Foundations of Civil–Military Relations: Deepening Civilian Training and Competence

As Eliot Cohen emphasized, healthy civil–military relations are not achievable through military efforts alone; they also require civilians who are trained and informed on military affairs. Civilian ministers and career bureaucrats in the Ministry of National Defense must possess the military insight and expertise necessary to lead and persuade the armed forces. While the current MND structure clearly distinguishes between active-duty/reserve military posts and civilian posts, this strict division hinders the realization of meaningful civilian control. To address this, policies should be introduced to expand civilian positions, redesign promotion and assignment tracks, and establish personnel and education systems that allow civilian officials to develop military expertise from early stages in their careers.

Members of the National Assembly and their staff must also move beyond interest in defense budgets and military-related incidents, and deepen their engagement with core defense policies such as military strategy and force development. Likewise, actors that serve as intermediaries between civil society and the military—such as the media, NGOs, and think tanks—must strengthen their interest, commitment, and expertise in military affairs. The Ministry of National Defense should actively support the defense-related activities of journalists, civil organizations, and academia to help foster a robust national defense community.

5. Conclusion: Civilian Control and the Maturation of Democracy

The 12.3 martial law incident provided South Korean society with a critical opportunity to reassess the current state of its civil–military relations. Although it was an unfortunate event, it should serve as a catalyst to strengthen democratic control over the military and to reestablish a sound framework for civil–military relations. The development of civil–military relations is ultimately a matter of democratic maturity. The initial aim of civilian control is to prevent the collapse of democracy. As the incident demonstrated, changing military behavior and institutionalizing democratic checks on the military are the most fundamental tasks. The next stage is the deepening of democracy, which involves ensuring democratic control over key defense policies such as budgeting, organizational structure, military strategy, and force development. The final goal is a fully institutionalized democratic society, in which civilian expertise in defense is strengthened and the civilian foundation of national defense is deeply embedded throughout society. Just as the pursuit of democratic consolidation has no final destination, the project of civilian control must remain a continuous and enduring task for any democratic society.