Professional Military Education as an Institution: A Short (Historical) Institutionalist Survey

This paper aims to take a step towards overcoming two lacunae in Professional Military Education (PME) literature. First, the lack of conceptualisation of what PME is and its relationship to military professionalism. Second, the fact that the vast majority of PME literature consists of studies concerning a single PME organisation, e.g. a specific military academy or college; there is almost a complete lack of national, regional and global studies of PME. The current paper takes a first step in overcoming the first lacuna by defining PME as an institution and taking a historical institutionalist approach to tracing the evolution of PME in the Western world. This new approach will also demonstrate how a sound conceptualisation of PME could contribute to overcoming the second lacuna.


Introduction
Despite its empirical richness, the Professional Military Education (PME) literature has been suffering from two major deficiencies. First, there is an almost complete lack of theoretical consideration as to the meaning and characteristics of PME as a concept as well as to its relationship to the often co-occurring concept of military professionalism (Davis 1980;van Creveld 1990;Libel 2010a;Libel 2016). Second, there is a significant lack of either national, regional or global studies. This has hindered systematic and comparative analysis of the evolution and diffusion of PME (Jalili 2019). The current paper attempts to take the first steps in overcoming these deficiencies in the literature. The main argument of the paper is that PME could be conceptualised as an institution, permitting its analysis through the theoretical approaches of new institutionalism.
This conceptual argument is demonstrated by introducing historical institutionalism as a suitable approach for comparative analysis of PME as an institution. The approach is used to conduct a short survey of the historical evolution of PME as an institution in the Western world. The paper outlines the main phases of this evolution, their characteristics and the critical junctures that defined the beginning and end of each phase. This paper should be considered more as a 'proof-of-concept' regarding the utility of the suggested approach than as a definitive study of PME as an institution.
The paper begins with a discussion of the lack of theoretical treatment of the meaning and characteristics of PME. This is followed by an introduction to how PME can be defined as an institution, and how this framing offers an advantage for analysing the origins of PME, its historical trends and the significance of its evolution. Special attention is paid to the crucial distinction between PME as an institution and PME as an organisation. The second section presents historical institutionalism as a theoretical framework for a comparative analysis of PME. The framework is then used to trace the general development of the PME institution in the Western world from the late 17 th century to the early 21 st century. The paper concludes with a discussion of the main findings and offers directions for future research.

What Is PME All About? Professional Military Education as an Institution
Although the term PME is used widely in the academic and military-professional literatures, it has two implicit significant deficiencies. First, the relationship between the military profession and PME has never SCANDINAVIAN JOURNAL OF

MILITARY STUDIES
Libel: Professional Military Education as an Institution 122 been either clearly defined or explored. Second, the term PME is often used loosely in reference to military education (ME) organisations of non-professional armed forces, e.g. in Israel (Libel 2013). These deficiencies could begin to be solved by defining officership as an institution, as its characteristics are well aligned with those of institutions, as defined within sociology as 'social rules, norms and ideas (Leitideen) that guide, but also restrain, social behaviour' (Ebbinghaus 2005: 6). The institution of officership in turn could be seen as one of a wider class of institutions of different ideal types of military command (Shamir 2011: 8-10;van Creveld 1987: 1-14), and the education which socialises candidates to the expertise, attitudes and ethics of the profession of arms as a (sub)institution. 1 By defining the military profession as an institution, PME can be seen as constructing and reproducing the wider institution of the military profession. Due to the role of officers as the command echelon of any armed forces around the world, understanding the continuity and change of a national manifestation of this institution is crucial for explaining the behaviour of a military force or elite (Crosbie, Lucas & Withander 2019: 41-42).
Therefore, the first deficiency described above is resolved as PME is redefined as an institution which sets the social rules, norms and ideas for the organisations tasked with the education of officers. Thus, there is a need to reconceptualise the commonly used term 'PME institutions' as 'PME organisations' in order to preserve the use of 'institution' to its sociological meaning. In addition, this makes it possible to overcome the second deficiency -distinguishing analytically ME, an inter-related or subset of the wider institutions of non-professional type command, from PME. As PME closely interacts with the institution of officership, i.e. the military profession, its existence or lack thereof within specific armed forces can be established in order to assess whether the armed forces in question should be classified as 'professional' or not, by establishing whether it has ME or PME. 2

Studying PME as an Institution: From Theory to Practice
Conceptualising PME as an institution is done by situating it within the new institutionalism literature. The latter is an umbrella term encompassing several schools (Immergut 2006;Steinmo 2008). Hall and Taylor (1996) have presented a common categorisation of historical institutionalism (HI), sociological institutionalism (SI) and rational choice institutionalism (RI). Each school approaches the fundamental institutionalist problematic -how institutions affect behaviour -differently. In spite of these differences, at a minimum, 'there is considerable agreement [italic in the original] among institutionalists in that they all see institutions as rules that structure behaviour. Where they differ is over their understanding of the nature of the beings whose actions or behaviour is being structured' (Steinmo 2008: 126).
When it comes to tracing the comparative evolution of an institution across a long time period, historical institutionalism is ideally suited to the task. It emerged in the 1960s and 1970s in response to 'group theories of politics and structural functionalism' that viewed the state as a neutral arbiter among competing interests (Hall & Taylor 1996: 5;Steinmo 2008: 153-158). As an alternative, historical scholars developed a conceptualisation of the state as an array of institutions capable of constructing the character and results of social and political conflicts. Cross-national analyses of public policy, adopting this approach, demonstrated how the interactions of institutions produce distinctive national trajectories (Hall & Taylor 1996: 6;Steinmo 2008: 157-158).
Historical institutionalist studies typically share five features. First, the relations between institutions and behaviour are conceptualised in broad terms. Second, emphasis is placed on the asymmetry of power in the operations of institutions. Third, path dependency and unintentional ramifications are emphasised in accounts of institutional development. Fourth, historical institutionalist scholars tend to combine historical institutionalist analysis with other approaches that emphasise additional explanatory factors. Fifth, as was mentioned above, the historical institutionalist literature has a strong comparative dimension (Hall & Taylor 1996: 8;Amenta & Ramsey 2010: 22, 26;Immergut 2006: 240-243). Moreover, historical institutionalist scholars perceive institutions as formal or informal procedures, routines, norms and conventions that are embedded in the organisational structure of political or economic relations (Hall & Taylor 1996: 6-7;Steinmo 2008: 150). The focus of such analyses tends to be on state-level institutions that structure conflicts and outcomes (Amenta & Ramsey 2010: 23, 25-26).
Hence, exploring PME from a historical institutionalist perspective involves analysing the organisational structures within which the institution is embedded, i.e., PME organisations, and how they construct and reproduce officership. The 'historical nature' of historical institutionalism is understood to be that of contextualising institutions in terms of time and space, with awareness of timely order in explanations that are based on path-dependent sequences (Immergut 2006: 242;Steinmo 2008: 150). Thus, the study of the organisational structures that uphold the PME institution must be based on tracing the timely order of their evolution and the events that locked developments on certain paths. This approach does well in explaining the 'what' and 'how' of institutional development, but it has difficulties explaining change due to the lack of agency in its explanatory arguments (Schmidt 2010: 10). As this study is a 'proof-of-concept' for the utility of the approach, it is focussed on the former and leaves the latter to future studies.
Historical institutionalist analysis often relies on the strongly inter-related concepts of path dependency and critical juncture. In regard to the former, '[t]he central claim of historical institutionalism is that choices formed when an institution is being formed, or when a policy is being formulated, have a constraining effect into the future … This dynamic occurs because institutions and policies have a tendency towards inertia; once particular paths have been forged, it requires a significant effort to divert them on to another course' (Greener 2005: 62). Thus, path dependency is 'the means by which the "historical" gets into historical institutionalism' (Greener 2005: 62). However, despite the fact that the longer an institution is locked into a certain path, the harder it will be for the institution to break away from this path, major institutional change does happen. This requires a major crisis or, in the words of the institutionalist literature, it occurs at a critical juncture (Capoccia & Kelemen 2007: 341, footnote 2).
Critical junctures are defined by Capoccia and Kelemen (2007) as: relatively short periods of time during which there is a substantially heightened probability that agents' choices will affect the outcome of interest. By "relatively short periods of time", we mean that the duration of the juncture must be brief relative to the duration of the path-dependent process it instigates (which leads eventually to the outcome of interest). By "substantially heightened probability", we mean that the probability that agents' choices will affect the outcome of interest must be high relative to that probability before and after the juncture. (Capoccia and Kelemen 2007: 348) Thus, critical junctures constitute rare moments in which agents have a wider range of policy options than usual, with the one to be selected having major ramifications for the following outcomes, producing institutional arrangements that in turn generate self-reinforcing path-dependent processes (Capoccia and Kelemen 2007: 341). Therefore, the analysis should begin with identifying the critical juncture that led to the emergence of the institution in the first place, as well as the following critical junctures that influenced their development. Once the critical junctures are identified, attention has to be paid to observing and explaining the path dependencies that resulted from each of them. The next section offers an example of this approach. 3 described in the following sections. The first act or phase, ' origins', was the establishment of military academies in the 17 th and 18 th centuries (Converse 1998: 1). This development of military academies established the foundation for PME, with the initiation of officer-commissioning institutions. The second phase, the 'Kriegsakademie era', began roughly in the early 19 th century with the emergence of an intermediate or mid-career tier. Resulting from the increasing organisational and technological complexities of contemporary armed forces, the academies started equipping selected officers with the knowledge and skills for key command and staff positions. The most famous and arguably best of these organisations, epitomising the military professional hallmarks of the era, was the Prussian-German War Academy (Kriegsakademie).
In the third phase, the 'strategic era', a joint and inter-agency senior tier of PME organisations was established. This resulted from the emerging understanding that war extended beyond the military domain and required senior officers to learn about other domains of national security, alongside public servants. Although appearing prior to the First World War, the idea that PME also needed to include non-military dimensions of security spread quickly only after the Second World War, which had demonstrated the need for this type of knowledge. Afterwards, the institution did not change markedly until the 1970s.
In the 1970s, the fourth phase, the ' operational renaissance', manifested in the emergence of a fourth tier in the form of advanced warfighting institutions (AWIs). These new institutions are focussed on the operational level of war and educate selected officers in the operational arts. These schools have now become the last tier that educates promising officers in the development and employment of military force, while war/defence colleges focus on strategy and related inter-agency cooperation. The fifth phase, 'PME as a system', originated from the critical juncture of the end of the Cold War. In response to a variety of pressures, senior headquarters began to transform the, until then, independent PME organisations into one often joint, coherent system.

Phase One -'Origins'
Officers, defined here as commanders who are tasked with force development and force employment, existed prior to the modern era. However, the idea that preparing commanders for war involves formal education did not exist prior to the 17 th century (van Creveld 1990: 7;Barnett 1967). This originated from a critical juncture on the borderline between the late Middle Ages and early modern Europe, leading to the first re-emergence of standing armies in Europe since Roman times (Gat 1989). The foundations of this critical juncture in European early modern history emerged from the replacement of the feudal system of military service with mercenary units during the 12 th -15 th centuries. While in the short term, the existence of large units of mercenaries enhanced the power of the king at the expense of the strong nobility, once the king ran out of money these units became a destructive threat.
This became horrendously evident in France during the Hundred Years War. Not surprisingly, the end of the war marked a turning point that put the nature of military force on a markedly different path. In the aftermath of the war, the French kings imposed a special tax to raise sufficient funds to turn the crown forces into a standing army with commanders appointed by the king (Howard 2009;Barnett 1967: 17). In spite of resistance from the French nobility to the royal usurpation of its traditional privilege to raise and command troops, many young nobles pursued service in the royal army. Two routes existed to becoming commissioned as an officer: (1) service as a personal aide at a court, or (2) as a volunteer gentleman with the troops. However, neither route equipped future officers with discipline or education. These were major deficiencies, as the technological development of gunpowder and artillery necessitated mathematical expertise. In other words, modern technology contributed significantly to the emergence of the idea that war draws upon a significant theoretical body of knowledge that has to be mastered and thus to be studied by officers (van Creveld 1990: 14;Barnett 1967: 18).
These technological changes also led to an increase in branch specialisation, logistical support and the size of formations, resulting in a significant increase in command-and-control challenges (van Creveld 1990: 14). As a solution, the French kings established military academies, creating indirectly and gradually the new institution of PME (Converse 1998: 5). This resulted in a fundamental transformation of the essence of command during the 17 th and 18th centuries. At this time, mercenary units were already being replaced by standing armies whose officers were public servants, enjoying steady employment, timely salaries and prospects of promotions. This led, however, to the loss of a feeling of camaraderie which characterised the mercenary armies, which had a unit culture in which seniority resulted from experience. Instead, the standing armies favoured a clear distinction between crown-appointed officers and ' all the rest' (Howard 2009).
The transformation of officers into 'public servants' provided another necessary condition for the professionalisation of military officership -a fixed focus on loyalty (Bond 1972: 8-9). The latter had two aspects: Loyalty to a political entity, which was manifested in the commissioning authority (the monarch embodying sovereignty, i.e. 'I am the state'), and to the military organisation in which an officer serves. Both were instilled in future officers via their socialisation in the newly established military academies. The latter materialised first in the form of the technical academies established in France by the late 17 th to early 18 th century (Converse 1998: 1, 5;Barnett 1967: 19). The academies were attended mostly by sons of bourgeois families rather than of noble ones. This was due to the fact that the majority of young nobles, who were considered naturally born martial leaders, disliked the idea of acquiring knowledge and intellectual skills as a prerequisite for being commissioned as commanders (Preston 1988: 272-273). The first technical academies were the École royale du génie de Mézières, established in 1748, and the Artillery School at La Fère, established in 1756. The first non-technical military academy, the École Royale Militaire, 5 was established in Paris in 1751 (Preston 1988: 274;Converse 1998: 5).
The École Royale Militaire admitted the sons of noble origin, ages eight to eleven, into an eight-year programme. Sons of the rich nobility were predominant among the students, although scholarships were provided to sons of bankrupted nobility. Upon graduation the cadets were commissioned as lieutenants. In 1776, following disciplinary problems the academy was shut down just to be reopened and transformed into the foundations of a reformed officer education system the following year. In its new phase, the academy trained the best performing graduates of ten preparatory provisional colleges. Those graduates of the École Royale Militaire who excelled in mathematics joined the artillery corps, while the others entered the ranks of the non-technical branches (Preston 1988: 274;Huntington 1957: 521-526;Guízar 2020).
The 19 th century witnessed the diffusion of this early version of the PME institution throughout Europe, manifested in its organisational form of military academies (Preston 1988: 274;Converse 1998: 5). This foundational phase also set the path of one of the chronic deficiencies that continue to haunt the institution to this day, although in a different form (Converse 1998: 6-7). This was the effort to integrate two contradictory ideas: (1) educating a large number of poor noblemen, and (2) advancing technical education. The attainment of each of these goals required different practices and faculties. The simultaneous pursuit of these two divergent goals usually resulted in obtaining neither. Thus, the indecision on this issue resulted in an eternal debate that has influenced PME ever since: Which topics should be included in PME, and how they should be taught? (Bond 1972: 10-11).

Phase Two -the 'Kriegsakademie Era'
The second phase of the PME institution's development resulted from a critical juncture originating in the French Revolution and the following Napoleonic Wars. Similar to the technological advances and the related organisational developments that preceded the emergence of military academies, the mass armies of the revolution were transformed under Napoleon into more organisationally complicated and larger forces than their predecessors of the Ancien Régime (Bond 1972: 7-8;Millotat 1992: 29). The new armed forces required not only the techno-tacticians produced by the military academies, but also higher-level experts, specialising in the integration of the different ' cornerstones' of the military force: combined arms (House 1984). The need to develop this expertise resulted in the emergence of a professional officer corps in European countries. The officer corps was developed by adding an additional organisational tier: the staff colleges. This development was woven into the closely related institution, the military profession, when gradually the career structure of officers and their promotions were institutionalised. This increased the importance of professional commitment, education and prolonged service, and decreased the influence of an aristocratic background in the recruitment and promotion of officers (Bond 1972: 7-8).
The most famous of the early staff colleges, representing the most admired qualities of 19 th -century military professionalism, was the Prussian-German War Academy (Kriegsakademie). Unlike most of its contemporaries, which were marginal organisations that often trained unpromising officers, the academy was the cornerstone of the Prussian-German military system (Muth 2011: 415). 6 It reflected the main characteristics of PME in this era. Moreover, the Prussian-German battlefield performance in the German unification wars and the two world wars is commonly associated in popular and military professional literatures with the academy, resulting in a formidable myth about its qualities. This, in turn, continues to inspire military reformers and has shaped the views of the desired character of PME organisations to this day.
The Kriegsakademie originated from the crushing defeat of the Prussian army to Napoleon in Jena in 1806. As part of a quick military reform led by Scharnhorst (White 1989), a Prussian cabinet decree of August 6 th 1808 declared that selection and promotion of officers during peacetime should be based on professional education and knowledge. The academy's objective was to ensure that all officers received a good general education followed by a sound professional one (Preston 1988: 276). This was a crucial aspect of the reform, which relied on the production of a highly selective, competent general staff corps. The academy produced officers who could instil and execute mission command (Auftragstaktik) within the armed forces. This new military elite became the 'brain of the army' (Wilkinson 1895). The academy was the last phase of the preparatory process of the group from which officers were selected for the general staff corps. The role of general staff officers in the Prussian-German system was quite unique among contemporary and later armies.
Prussian, and later German, general staff officers had two unique responsibilities. First, the general staff officer relieved the commander from dealing with the technical details of staff work. Second, and more importantly, the general staff officer's main task was to advise the commander on every issue. Thus, he and his commander had a mutual responsibility for the relevance of this advice (Millotat 1992: 19). The general staff officer carried out his duties according to the command-and-control philosophy of mission command. Unsurprisingly, due to the educational requirements to perform these tasks, those who made it to the general staff officer ranks were almost always alumni of the academy. Admittance to the academy was dependent on merits (Millotat 1992: 30), i.e. superb performance reports, superiors' recommendations and the passing of a rigorous and intellectually demanding exam. While only a fraction of the officers taking the exam made it into the academy, preparation for the exam which could take up to four years resulted in a general increase in the abilities of the Prussian-German officer corps. 7 The academy began as the General War School (Allgemeine Kriegsschule), established in 1810 (Millotat 1992: 27), and was subordinated in 1819 to the Inspector General for Military Education and Training. 8 The school advanced PME in combined arms operations through a three-year curriculum with a scientific, rigorous approach. It was renamed the War Academy (Kriegsakademie) on October 1 st 1859 (Millotat 1992: 28). Until 1870, its pedagogical approach mimicked that of the universities of the era, i.e. didactic lectures (Millotat 1992: 36). Students had on average 20 weekly lecture hours on mainly non-military topics delivered by faculty that included both university professors and general staff officers (Millotat 1992). A major change took place in 1872 when the academy was placed under the supervision of the Chief of the General Staff. As a result, both the curriculum and the faculty became predominantly military, with the latter consisting of general staff officers who taught alongside their routine duties (Millotat 1992: 37). Despite its fame, the actual performance of the Prussian-German system, and the achievements of its graduates, was less efficient than its image due to an over-concentration of practical military skills rather than military theoretical studies (Preston 1988: 276-277). However, the Kriegsakademie myth did contribute to the diffusion of staff colleges throughout Europe and beyond in the late 19 th to early 20 th century (van Creveld 1990).

Phase Three -the 'Strategic Era'
Unsurprisingly, the First World War constituted a major critical juncture in the history of war, and naturally also for the PME institution. The war demonstrated that the operation-focussed institution did not prepare officers, in particular senior ones, for the new industrialised nature of war. As a result, the institution had to adapt, resulting in the adoption of pre-First World War structural innovation -an addition of a tier of PME. This new tier of joint, inter-agency senior colleges was added to the first tier, military academies, and second mid-career tier, staff colleges. The first joint, inter-agency defence or war college 9 was the Imperial Defence College (IDC), which was established in London in 1927 (Masland & Radway 1957: 143). It resulted from a growing recognition among senior British decision-makers that their colonial experience indicated a need for better coordination and understanding between the military and non-military apparatus in regard to national security. The college's first class consisted of 32 students with the ranks of lieutenant colonel and colonels and their equivalents from the public service and the British dominions. The curriculum included courses on British and imperial defence; the influence of political consideration on war management; economic, social, industrial and financial resources of Great Britain and the Empire; and policy and foreign policy (Gray 1977;Stewart 2018).
As the college had a very small staff -a commandant, three directing staff (DS) members from the services and a civilian consultant -it relied on a series of officers or officials as guest speakers. The teaching relied partially on seminar discussions in small groups (syndicates) as well as assigned reading and writing tasks (Gray 1977). Alongside its joint and inter-agency nature, these pedagogical measures became the main legacy of the college (Davis 1980;Libel 2010a). The example of the British Imperial Defence College was hardly copied by other countries prior to the Second World War (Masland & Radway 1957: 143). However, following the total nature of the Second World War, the institutional innovation diffused rapidly around the world (van Creveld 1990: 82).
The adoption of this structural innovation was reinforced by World War Two and the early Cold War. Symbolising the shift of strategic leadership in the Western world to the US, the path set from this critical juncture originated in the American armed forces (Libel 2010a). Facing the emerging Soviet threat, the US maintained for the first time a large peacetime standing army. Its officer corps included a large number of combat veteran, mid-career officers, who could potentially become an expanded core. Having been promoted during wartime, the majority of these officers lacked systematic professional training. As a response, the American armed forces changed the institutional role of the staff colleges to educating these mid-career officers. Up to this point, Western staff colleges generally had not been used to educate commanders, but to train a small number of staff officers (van Creveld 1990: 78-79).
Thus, although the institutional three-tier structure remained intact, the character of the staff colleges changed significantly as the resulting path made attendance at a staff college virtually mandatory for midcareer officers. This was reflected in the increase in the number of assignments reserved for graduates in the late 1940s to early 1950s (van Creveld 1990: 78-79). As a result, the level of PME of those rising to senior ranks and attending a senior-level college improved significantly. However, the ten-month curriculum of both the staff and war colleges has continued to suffer from a tension that has been intrinsic to the PME institution since the establishment of the first military academies in the 18 th century: a tension between training and education, theory and practice, military and non-military affairs. By the 1960s, these tensions reached a breaking point, at which the colleges concluded that it was impossible to provide a ' one-size-fitsall' programme that meets the needs of all the students. As an alternative, military staff and war colleges began to introduce a mandatory core programme alongside a variety of electives. In the 1980s, the curricula began to include joint content (van Creveld 1990: 83-84).
The ability of the college curricula to realise their potential was, however, structurally limited. Partially, this resulted from the unsatisfactory academic qualifications of military instructors and the shortage of qualified civilian faculty members. The former usually held ranks similar to those of their students, and the basis for their employment as faculty lacked clear criteria. Moreover, due to a high turnover, they did not have time to develop pedagogical proficiency. Civilian faculty members were mostly young PhDs who often had not succeeded in finding academic employment elsewhere, and whose further professional development was curtailed by the heavy teaching load. Neither group had control over the design of the courses they taught (van Creveld 1990: 81-82). 10 Thus, the maturation of PME in the United States, and most other Western countries, into three-tier institutional settings did not always translate into significant improvements in the quality of the PME experience. This began to change with the appearance of the AWIs.

Phase Four -the 'Operational Renaissance'
The emergence of what Winton (2005) termed Advanced Warfighting Institutions (AWIs) resulted from the by-now famous change that occurred during the late 1970s and early 1980s: the complete overhaul of the technology, doctrine, organisation and ethos of the American military approach for the preparation, planning and conduct of operations (Naveh 1997;Bronfeld 2008;Terriff 2006). Much like the technologicalpolitical-doctrinal innovations of the early 19 th century that led to the establishment of the Kriegsakademie, the new developments required the three-tier PME institutions to adapt in order to prepare a new military operational elite. This resulted in 'the formation of institutions devoted to the advanced study of the art and science of war' (Winton 2005: 7). In response to the increasing demands for expertise and skills from operational-level commanders and staff officers, leading armed forces added a fourth tier of PME. Situated between the command and staff colleges and the senior-level colleges, the AWIs constitute the apex of a purely military education, i.e. in contrast to the strategic level. The first of these schools was the US Army's School of Advanced Military Studies (SAMS) (Winton 2005). Established in 1983, it constituted practically a second year of studies for selected graduates of the US Army's Command and General Staff School (CGSS).
The success of SAMS led to the establishment of several similar organisations. The most famous ones are: the US Air Force's School of Advanced Air and Space Studies (SAASS) established in 1990 (Libel & Hayward 2010); the British Army's Higher Command and Staff Course (HCSC) established in 1988 (Libel 2010a: 185-205); the US Marine Corps' School of Advanced Warfighting (SAW) established in 1990 (Libel 2010a: 110-128); the Israeli Operational Theory Research Institute's (OTRI) Advanced Operational Command and Staff Course 11 (AOCSC) established in 1996 (Libel 2010b); and the US National Defense University's Advanced Joint Warfighting School (JAWS) established in 2004 (Libel 2010a: 110-115).

Phase Five -'PME as a system'
The final act so far in the evolutionary play of the PME institution in the West resulted from the end of the Cold War. Faced with multiple operational, political, social, economic and technological pressures, Western armed forces turned to their PME organisations as a solution. The latter were seen as means to improving both their operational effectiveness and harmonisation of civil-military relations. This set a new path of continuous restructuring of Western PME organisations from previously independent organisations into one formal, structured, systematic and comprehensive system of PME under specialised, designated commanding authority (Libel 2010a). This consolidation shifted the previously mostly independent single service PME organisations , into a consolidated service (and often) joint PME system under one centralised headquarters.
These headquarters set overall policies and increasingly transformed the individual organisations into one with joint, inter-agency and allied faculties, student bodies and curricula (Libel 2016). These changes were intended to adapt the PME organisations to the realities of contemporary command and staff work, i.e. operating in joint, inter-agency and multinational settings. Hence, contemporary Western PME organisations display an increasingly joint character at the expense of a service one. Moreover, the increasing presence of civilian and foreign faculty members and students in PME organisations has reduced the military and national identities of the PME organisation. The reality of a consolidated and coordinated service system means that these processes take place across-the-board and are mostly executed in a top-down manner. Hence, these changes in the PME organisations have had a major influence on the transformation of the PME institution and, through it, on the character of Western officership.
In addition, increasingly, the consolidated PME systems have gained academic accreditation, with a variety of arrangements for employing civilian academic faculty alongside the military one (Barrett 2009;Callado-Muñoz & Utrero-González 2019;Constantineau & Last 2015). 12 For example, American military colleges tend to hire civilian PhDs, often retired military officers, who support the accreditation of the military colleges (Foot 2001;Libel 2010a: 321-322). Alternatively, the Defence Academy of the United Kingdom has contracted the academic component of its colleges' teaching to civilian universities, which have established their own departments within the academy colleges. Academic faculty teach alongside and in coordination with the military staff (Libel 2016: 43-49).
Although academisation of PME organisations seems to be the trend in the Western world, significant national and regional variations exist, and their influence on the military curricula and integration within the civilian higher education systems varies (Libel 2016: 213-214;Callado-Muñoz & Utrero-González 2019;Constantineau & Last 2015). 13 Moreover, the academisation of PME organisations has to some degree changed the content, pedagogy and practices and norms of military curricula. Combined with the changing composition of faculty and student bodies described above, the contemporary Western PME institution, and by extension officership institution, has become increasingly security-oriented rather than having a militaryprofessional orientation (Barrett 2009;Libel 2016: 210-212).

Conclusion
The current paper seeks to overcome two implicit lacunae in the PME literature. The first is an almost complete lack of discussion of what PME is in theoretical terms, and how it relates to the military profession. The second is the lack of national, regional and global histories of PME. Despite the prolific literature on individual PME organisations, few studies have attempted to provide an overview of even national evolutions of PME. If we are to begin to overcome these deficiencies in the literature, this paper argues, there is a need for a much better conceptualisation of PME and its relations to officership. Theory building will support sound, hypothesis-driven research designs; it will also help to frame and guide the rigorous comparative historical analyses that are desperately needed.
The paper has demonstrated the utility of historical institutionalism by defining PME as an institution and studying its evolution in the Western world. By defining officership as an institution and PME as a related institution crucial for the social construction of the former, it becomes possible to draw upon the extensive new institutionalism literature. Anchoring the theory building concerning PME within a well-established and sophisticated literature could save social scientists the need to reinvent the wheel. Interactions between those who work on civil-military relations issues and the wider social science field have become too rare over the last decades (Libel 2020). However, better dialogue is also required between the social scientists and historians who together produce most of the writings on PME.
Although those who either work in or study PME organisations have a good overview of the general landscape of the evolution of PME, the details of the story are often obscure. Closer collaboration between social scientists and historians can combine methodological skills and detailed knowledge to accumulate comprehensive data. This is a necessary basis for reaching a true picture of the timely order of development, direction of influence and interrelationships between PME organisations across the world. Moreover, there is a desperate need to do much more to bring scholars and practitioners from the non-English world into the collaborative effort to trace the development of PME outside of the Western world. Despite some commendable exceptions (e.g. Jalili & Annen 2019; Last, Emelifeonwu & Osemwegie 2015), knowledge about PME in the global South is much more limited than that of the Western world.
No doubt, some -if not many -readers will find these arguments provocative. However, this should be seen as an invitation to enter into a dialogue that is required for making the study of PME as global and historically detailed as the phenomenon of PME itself.