Ukraine’s third wave of military reform 2016–2022 – building a military able to defend Ukraine against the Russian invasion

ABSTRACT This article explores an important and often overlooked element of Ukraine’s ability to defend itself against the Russian invasion in February 2022 – the adoption of a modified western transformational model of military reform – which has focused on mass and building a western style NATO interoperable and trained military. This article argues that Ukraine’s military reform since 2016, in particular the focus on Command and Control, the development of an NCO Corps and Special Forces as well as clear procurement priorities have created the enabling conditions for the development of a flexible and adaptable military force, able to limit Russia’s battlefield success and bring the fight to the enemy. Despite this progress, however, a recurring problem facing the Ukrainian military, that is likely to continue in the future, is how to balance the ongoing requirement for mass against the urgent need for military modernisation.


Introduction
Ukraine's ability to survive the brutal onslaught of a full-scale Russian military invasion in February 2022 might appear to have been little short of a miracle. Ukraine's military has stopped the enemy from achieving its key goals, successfully prolonged this conflict, significantly increased the costs of this war for the Russian Federation, and more recently has also made some notable progress in retaking territory. There are of course many reasons for this success. These include the political, economic, and military support of many western nations, the unity, strength, and determination of the Ukrainian people and the emergence of a strong and charismatic Ukrainian war leader, President Zelensky. It is also widely recognised that Russia's miscalculations and military failures have also played a crucial role in creating the enabling conditions for Ukraine's military success. 1 This article explores another important, and often overlooked, element of Ukraine's successthe reform and modernisation of its military. It looks at how Ukraine reformed and built up its military forces prior to 2022, what its priorities have been and what accounts for its success. Ukraine made sufficient progress in a number of key areas, and that this created the enabling conditions for the development of a flexible and adaptable military force, able to limit Russia's battlefield success and bring the fight to the enemy. In essence, Ukraine's adoption of a modified western transformation model of military reform, with an emphasis on bringing its forces up to NATO standards, 2 on selective procurement, all combined with a focus on mass, has given the Ukrainian Armed Forces (UAF) significant levels of flexibility and adaptability and the ability to seize the initiative even when confronted by a militarily superior force.
In making this argument, the article is divided into three sections. The first examines Ukraine's military reform and argues that Ukraine has moved away from the government's stated goal of adopting a transformation model of military reform and has instead adopted more of a hybrid model that retains the best elements of the former, but also recognises the need for massa large standing forcegiven its unique geostrategic environment. The second section examines Ukraine's adoption of key elements of the transformation model including improved command and control, the introduction of an NCO Corp and a strong focus on the development of its special forces, all of which has not only increased Ukraine's combat power, but also the ease and speed with which Ukraine has absorbed and utilised western military equipment and support. Over the last few years Ukraine's adoption of a process of what might be termed "smart" or "tailored" procurement -filled important gaps that would prove vital in allowing it effectively to adopt a defensive and latterly more offensive military strategy. Ukraine also went into this war with a battle-hardened military that has learnt many lessons from fighting the Russian backed separatists in the eastnot least of which the need for a large standing army with decentralised and flexible command structures. The third section looks at some of the problems Ukraine has faced in reforming its military, the most important of which has been the difficultly in balancing the cost of building and sustaining a large standing force with the need to modernise and upgrade its weapon systems.
The analysis of Ukraine's military reform up to the Russian invasion of 2022 is important for two key reasons. First, it says something significant about the enduring challenges of military reform facing all states in the technological age where the threats are multifaceted. The Ukrainian experience demonstrates that smart decisions can be made, even on a relatively limited budget that can set up the enabling conditions for success even when dealing with an existential threat from a much more powerful neighbour. Second, the ongoing war in Ukraine also calls into question the continuing relevance of the transformation model adopted by so many militaries around the world. Ukraine's attempt to build more of a hybrid approach to military reform, which adopts the best elements of the transformation model, but combines this with a more traditional approach, has proven to be crucial to its very survival as a state. The adoption of a more bespoke and tailored transformation model of military reform from 2016, which includes an emphasis on mass, has made the Ukrainian military more resilient and adaptive than expected.

Ukraine's military reform
Since its independence in 1991, Ukraine's military has gone through three stages. The first, which ran from 1991 to 2006, was one of systematic neglect and decline, in which the UAF shrank in size and capability. 3 From 2006 to 2014 Ukraine entered its second stage of military reform, which was heavily influenced, at least on paper, by the transformation paradigm: a model of war that leveraged such new technology as digitisation, precision guided munitions and new sensors and command and control infrastructure through innovative new concepts and force structures. 4 In essence, the aim of this approach was to move away from the large military systems of the Cold War where mass would be replaced by smaller forces that were more agile, mobile, flexible, lethal, and versatile. 5 As part of its military reform process between 2006 and 2014, Ukraine had ambitious plans to build a "new type of army" one that was "mobile, professional trained and fully equipped." 6 Under these plans, the UAF was to be significantly downsized, and conscription was ended to allow the creation of a much smaller fully professional force. However, by 2014 it had become clear that this model of reform was beyond the capacity of the Ukrainian state to fund and implement.
More importantly, with the emergence of the conflict in the Donbas, the UAF was not able to meet the demands placed upon it. In the initial stages of what the Ukrainian government termed its Anti-Terrorist Operations (ATO) against the Donetsk and Luhansk separatists, the Ukrainian army struggled to deploy adequate numbers of properly trained and equipped forces. The financial and political neglect of the UAF meant that Ukraine could deploy only 6,000 combat ready troops in early 2014 out of a potential force of 130,000 personnel. 7 This was because Ukraine was badly hit by the economic crisis in 2008 and as a result, its defence spending failed to match the stated transformational ambitions of building a modern professional military. In light of these economic challenges, Ukraine's defence budget dipped to an all-time low of 0.79% of GDP in 2009 and remained at less than 1% over the next few years; which was simply insufficient to sustain, let alone modernise, its forces. Political instability and in-fighting during this period also had a negative impact on military transformation. In the run up to the Russian annexation of Crimea, military reform became hostage to political infighting, coalition building and constitutional wrangling amongst major political parties and actors in Ukraine. As a result, the government failed to provide either the finances or commitment necessary fundamentally to transform the UAF. The challenges facing the UAF in light of the growing conflict in the east, therefore forced the government to adopt a more creative and pragmatic approach to military reform, which retained elements of the transformation model, but also signified a return to mass and positional warfare.
In an attempt to address the challenges facing the Ukrainian military in the east, the acting President, Oleksander Turchynov, reinstated military conscription in May 2014, just months after it was scrapped by the former President, Viktor Yanukovych. 8 The return to conscription represented a move away from the officially stated, but clearly unfulfilled plans to develop a small professional standing force, and essentially opened the way for the adoption of more of a hybrid model of military reform. The adoption of conscription was in many ways an inevitable by-product of the type of high-intensity conflict the UAF fought in the east in 2014 and into 2015. The battle of Ilovaisk in August 2014 where a force of mainly volunteer Ukrainian battalions, supported by the UAF, failed to hold a strategic railway junction in Donetsk, highlighted not only the brutal nature of this war, but also just how problematic Ukraine's previous model of military reform was given the type of battle the UAF were fighting. 9 Ukrainian forces made four unsuccessful attempts to take Ilovaisk facing heavy and sustained fighting before its forces were cut off and then massacred. 10 Ultimately this battle demonstrated the importance of mass, reserves, and the need for a large stockpile of military hardwarenone of which Ukraine had. By 2015, it had become increasingly clear that the war in the east was not the rapid and mobile warfare that the UAF had been conceptually and structurally preparing for, at least on paper, since 2006. Instead, the UAF faced a highly attritional, and by mid-2015 an increasingly static and unremitting, conflict that required a large standing force. In light of these challenges, there was a general recognition in Ukraine that key elements of the transformation model of military reform would need to be shelved, in particular the reliance on a small professional force. In recognition of Ukraine's new strategic environment, in 2016 the Ukrainian Minister of Defence stated that a contract army would never be able to win the war in the east and that it would be "irresponsible" for Ukraine to return too quickly to a professional army. 11 Given the existential nature of the conflict in the east, military reform was essentially put on the back burner until 2016.
In the interim years the UAF evolved in a more organic ad hoc manner modifying the transformation model of reform in three key ways. The first change to the model was the mobilisation of Ukrainian society; something that Ukraine has again drawn on heavily since the Russian invasion in 2022. Due to the systematic failure of the previous reform process to effectively fund the military, as well as the high costs of fielding a much larger army, between 2014 and 2016 Ukrainian civil society emerged as a key player in financing and supplying the UAF. Official figures suggest that civil society provided the UAF with almost 4% of the Ukrainian defence budget in donations, logistics support and humanitarian assistance in 2015. 12 A second change was that the Ukrainian government authorised the formation of militias, organised and funded by individuals and groups. As a result, almost 50 volunteer battalions, who were not an official part of Ukraine's military structures and operated alongside the UAF, were set up comprising almost 10 thousand fighters. 13 Throughout 2014 and into 2015 these volunteers played a vital role in containing the separatists performing a range of tasks from police functions to combat operations. They have now largely been integrated into the UAF, although this process has not been without some challenges. 14 The final adaptation to the transformation model was the introduction of conscription and the recognition of the need for a large standing force. The return of conscription and the announcement in February 2016 of the launch of the seventh wave of mobilisation increased the size of the UAF to 250,000 personnel.
This allowed the military to successfully field 53,000 service personnel by 2015 in the ATO operational area in the east. 15 After a two-year interregnum, where the UAF were allowed to develop more organically, military reform was put firmly back on the agenda and Ukraine entered the third stage of its transformation. In 2016, the Ukrainian government published the new Strategic Defence Bulletin, which laid out its plans for reforming the military over the next four years. President Poroshenko described the new Strategic Defence Bulletin as a "landmark programme of reform … which is doing what hasn't been done in 25 yearscompletely rebuilds the Armed Forces." 16 The Bulletin outlined two new key priorities, which would have a profound effect on creating the enabling conditions for Ukraine's defence against Russia. The first was to bring the UAF up to NATO standards; the second was to strengthen democratic civilian control in the defence sector. The former was a recognition that Ukraine's destiny lay in seeking closer relations with and membership of NATO and the latter was a recognition of the vital role played by Ukrainian society in the conflict in the east. This initial plan was followed by the State Programme for the Development of the Armed Forces 2017-2020, which outlined how this reform would be implemented. A year later an additional document was published, the Law on National Security, which replaced the existing law on defence planning, and created a framework to coordinate and simplify Ukraine's defence planning and implemented civilian control over the military. In 2020 and 2021, Ukraine also updated its National Security Strategy and its Military Security Strategy. The National Security Strategy clearly identifies Russia as a long-term threat to Ukraine's security and emphasises the need to develop closer relations with the EU, NATO, and the US. While this reform process would usher in a new era for the UAF, with increased emphasis on bringing the armed forces into alignment with western standards and making them interoperable with both EU and NATO forces, one of the key challenges was that military reform was essentially un-costed and as a result priorities were often unclear. Without laying out explicitly the costs of reforming the armed forces and garnering sufficient civil and political support, the plans to build a modern well-equipped interoperable military in Ukraine were seen by many as little more than "smoke and mirrors." And while this long-standing problem of not laying out a clear budget and plan for military reform remained, some progress was made which did, nonetheless, create the foundations and some of the enabling conditions for Ukraine's military success in 2022.

Ukraine's new hybrid transformation model
The adoption of Ukraine's new hybrid transformation model has proven critical in allowing Ukraine to defend itself against the Russian invasion; in particular, the introduction of new structures and clear priorities have created the enabling conditions for Ukraine's resilience. These include the development of a more effective command and control structure, the development of an NCO Corps and Special Force Operators, as well as the pursuit of specific procurement objectives. Other elements of military reform introduced before the invasion which are generally recognised as important to Ukraine's success include the substantial increase in training, advisory and intelligence support from NATO countries, which have played an important role in increasing the UAF warfighting potential, as well as the development of Ukraine's reserve system and the setting up of Territorial Defence battalions. 17 Through classes, drills and annual exercises NATO and its members played an important role in training the UAF prior to the Russian invasion. The Canadians for instance, trained Ukraine's Rapid Response Brigade in the summer of 2021 in urban warfare, field tactics and battlefield medicine. 18 A few months later four thousand Ukrainian troops took part in the annual military exercise, Rapid Trident, aimed at boosting combat readiness, Ukraine's defence capabilities and interoperability. Since 2014, the UK also trained 22 thousand Ukrainian troops in medical, logistics intelligence and infantry skills as part of Operation Orbital. While western training is often seen as a key enabler to Ukraine's recent battlefield success, the most important element of Ukraine's military transformation has been in improving its command and control. The UAF learnt important lessons about the critical role of command and control in the east and made significant progress in building a more effective system over the last nine years. After several weeks of fighting in and around Debaltseve in 2015, pro-Russian separatists surrounded the city forcing Ukrainians forces to withdraw. An important insight from this battle was that the separatists coordinated their action much better than the Ukrainians. The ability to exercise command and control, by communicating and coordinating actions, is an essential element of combined arms operations and was vital to the Russian backed separatist's success. 19 Learning these lessons Ukraine does appear to have had some notable success in developing a devolved system of command and control, which is widely recognised amongst western militaries as representing best practice in terms of effective command. 20 Mission command is a style of military management that gives more authority to soldiers on the ground. It is the process of following strategic objectives set by commanders whilst giving lower ranks tactical autonomy and is standard NATO doctrine. Commanders state their intent, what the principles and objectives of a mission are, and then delegate responsibility for achieving it to more junior officers or NCOs, allowing them to exercise their own initiative and judgment. Mission command is widely recognised as speeding up military decision-making and allows for a more flexible and creative response at the tactical level. 21 The importance of developing mission command by the UAF was recognised in the 2021 White Book, which provides an annual assessment by the government of the progress Ukraine has made in reforming its military. It stated that effective command and control "must not only issue orders and directives, but also enable the commander to apply mission command with the ability to deviate from a specific plan if necessary; encourage disciplined initiative within the commander's intent." 22 Facilitating this flatter and more dynamic command structure has been the promotion of a new generation of Ukrainian leaders, battle hardened from years of fighting Russian in the east who have learnt to be flexible, trust their subordinates and delegate decisions to commanders on the ground. The leadership of Ukraine's Commander in Chief, Valeriy Zaluzhny, has been widely credited with enabling the UAF to "adapt quickly with battlefield initiative against the Russians." 23 Zaluzhny worked his way up from commanding a platoon to leading the country's forces on the eastern front and in that role encouraged more agile decision-making, pushing authority downwards. Whilst one inspirational leader alone cannot change a military's command style and procedures, the UAF's collaboration and training with NATO forces under Zaluzhny's leadership has gone some way to moulding "a group of professional-minded Ukrainian officers that aspired to Western standards and helped build a decentralized, empowered, more agile way of warfare." 24 In essence, the UAF have created a mission command culture where leaders push authority, decision-making and responsibility for execution down into the ranks "so that all sergeants and lieutenants would know what to do when the [next] invasion came." 25 During the conflict with Russia, the UAF has adopted NATO-style principles of command, such as the delegation of authority to local command as well as to junior and lower-level officers including NCOs. 26 The ability of the UAF to launch a surprise attack in the northeast catching Russia forces off guard taking back huge swathes of its territory can be explained by many factors, one of which is the adoption of a command structure that allows individual commanders the freedom to make decisions at every level much quicker than the Russian forces. 27 The UAF have demonstrated flexibility and a willingness to adjust operations due to changing circumstances, particularly at the unit level. 28 In essence, Ukraine has, perhaps out of military necessity, adopted a dispersed command structure, allowing each operational command to co-ordinate and initiate operations according to local conditions. 29 Giving lower level commanders the right to make their own decisions has also facilitated ad hoc coordination between forces on the ground, without the need to co-ordinate via headquarters. Hanna Shelest has claimed that the Ukrainian defence of Mariupol and Azovstal was an example of this type of joint co-ordination and co-operation where decisions were made independently by Ukrainian commanders. 30 An important enabler in terms of facilitating mission command and a much flatter command structure has been the development by Ukraine of a professional corps of non-commissioned officers, or NCOs. Empowered NCOs have given Ukraine a clear advantage in the war with Russia. The failure by the Russians to begin any systemic effort to stand up a professional NCO Corps has meant that the Russian military fielded an inflexible, heavily centralised and hierarchical military lacking the ability to engage in effective mission command. Marine Corps General Frank McKenzie, Commander of U.S Central Command, highlighted this problem at the start of the conflict when he stated that "the one thing the Russians don't have which is sort of the key of the U.S. joint force, is the middle management level; the NCO and Staff non-commission officer level that really forms the background of our military." 31 As a result, the "Russians are practicing a top-down, very, very top-heavy directive in nature-sort of, settled orders coming from the top, which is not necessarily the best thing to do in a dynamic battlefield." 32 The UAF on the other hand have had some notable success with developing professional NCOs "due to an early push of reforms and the dynamic of war, where a lack of officers during the conflict in the east bolstered NCOs' opportunities to step forward." 33 During the conflict in the east Ukraine moved decisively away from the less effective Soviet approach where a sergeant is merely a link between soldiers and officers, with the rank sometimes given to conscripts. As a result, by 2017, all fire teams, squads or platoons in the east were commanded by skilful and experienced sergeants. 34 Despite this commitment to developing an effective NCO Corps, Ukraine did face some initial challenges with the retention of sergeants as a result of the delay in the introduction of a reform bill, which would establish new western style military ranks and as importantly, also raise soldier's wages. By the end of 2020 Ukraine had begun to address these issues with the introduction of seven new NCO ranks and increased pay with the aim of retaining experienced sergeants. 35 In 2020, Ukraine also adopted the Concept of the Development of a Professional Sergeant Corps, under which more than two thousand officer posts were replaced by sergeants. 36 Under this plan, officers would deal more with planning daily activities, training, and combat tasks and the function of practical implementation of decisions would be delegated to NCOs. Ukraine's investment in developing its NCO Corps has proven important in decentralising battlefield decision making and thereby speeding up the Ukrainian response to Russian action, allowing for faster and more creative decision-making from Ukrainian forces. 37 The importance of Ukrainian NCOs in defending Ukraine against the Russian invasion was spelt out by Chief Master Sergeant of the Ukrainian Air Force, Kostiantyn Stanislavhcuk, who claimed that during the conflict with Russia, Ukrainian sergeants "without waiting for instructions from above, took the initiative to conduct independent small operations and act independently and resourcefully." 38 A key priority of Ukraine's military reform prior to the conflict, that has also had an effect on Ukraine's combat effectiveness, has been the development of Ukraine's Special Forces and bringing these up to NATO standards. During the conflict in the east, the effectiveness of Ukraine's Special Forces (SF) had been hampered by the lack of a dedicated command structure, which meant that they were treated as ad hoc infantry and supplementary forces and rarely used for specialist operations. 39 In light of these challenges, Ukraine's SF were strengthened and placed under a separate command structure and their training and provision of equipment has been prioritised. Prior to the Russian invasion Ukrainian SF had augmented their capabilities by developing a land, air, and maritime component. 40 Ukrainian army SF units include the 3rd and 8th regiments, based in Kirovograd and Khmelnytskyi and are tasked with undertaking direct action and special reconnaissance missions. Each unit is made up of 300 service personnel and is subdivided into companies and platoons with SF operators specialising in combat engineering, heavy weapons, communications, and combat medicine. 41 Also included within the Ukrainian SF land element is the 61 st Jager Infantry Brigade, which was established in 2019 to provide a capability similar to the US Rangers. The Brigade specialises in intelligence gathering and force protection missions and is also capable of independent missions. The Ukrainian Navy's SF units include the 140th Special Purpose Centre, the 801 st Anti-Diversionary Detachment and 73rd Marines Centre. These forces have been focused on security in the Black Sea. Ukraine's dedicated SF air component was stood up in 2020 to support army and navy SF units. Equipped with helicopters and transport aircraft the air component's aim was to facilitate the insertion, extraction, and resupply of small unit teams across Ukraine. As well as developing the necessary structures, Ukrainian SF had been amongst the main beneficiaries of western support prior to the invasion of Ukraine. The US in particular has been actively involved in partnering and training Ukrainian SF effectively transforming the Ukrainian approach to warfare, by improving their selection process, access to equipment and establishing a more rigorous training programme. 42 Ukrainian SF also regularly participated in NATO exercises, including Combined Resolve Exercises in 2021 in Germany, which aimed at developing unconventional warfare skills. 43 In a clear sign of the progress Ukraine has made in developing its special forces, in particular its interoperability and capabilities, Ukraine's 140th Special Operations Forces Centre passed NATO certification in 2019, allowing it to deploy as part of the NATO Response Force. 44 These deployments have given them access to state-of-the-art equipment including night visions goggles, portable real-time intelligence, surveillance, and reconnaissance and communication devices, significantly enhancing their effectiveness in a contested battlespace. 45 As the conflict in Ukraine has unfolded, there is growing evidence that these developments had significant implications for the current war. Ukrainian SF have played an important supporting role in operations. For example, in late February, working closely with Ukraine's artillery battalions they repelled advancing Russian mechanised forces in Kyiv's suburbs, especially in Bucha, Irpin and Hostomel, causing heavy Russian losses. 46 In other areas Ukrainian SF have engaged in more irregular warfare behind enemy lines, attacking logistics, including supply convoys and Russian outposts such as the Chornobaivka airfield near the Russian occupied city of Kherson. 47 It is also clear that Ukraine was able to mount an effective defence against the Russian invasion because its weapon priorities were more focused during this last stage of military reform with a clear focus on artillery and the procurement of anti-platform weapons. After 2014 the UAF have prioritised recovering their artillery and missile capabilities, which had been systematically reduced under President Yanukovych. At the start of the conflict with the Russian backed separatists in the east, Ukrainian artillery had structures, equipment and manpower totally unsuitable for battle. 48 Further incentivising the UAF to rebuild, artillery was also proving to be a decisive weapon in terms of lethality in the east. In the first two years of the conflict Russian and Ukrainian artillery had killed around nine thousand troops and civilians on all sides and injured around 21 thousand. 49 In addition, it became clear that the employment of indirect fires, the use of long range artillery and rocket fire, would be a key weapons used by the Russian backed separatists to attack the UAF. 50 In light of the clear importance of long-range firepower, Ukraine created five new artillery brigades and a separate artillery regiment for both the Army and the Ukrainian Navy. In addition, all new combined arms brigades in the Army, as well as the marines received their own brigade artillery groups, which meant that by 2019 the UAF had doubled the number of artillery battalions. Estimates suggest that by the start of the Russian invasion in 2022, the UAF fielded the largest artillery force in Europe after Russia. 51 As well as increasing the number of artillery and units, the UAF also introduced qualitative improvements during the third stage of military reform, which have increased the lethality of their firepower. This has included artillery locating radars, battery command and control systems, and, to improve the efficiency of the artillery units, drones were also introduced for forward observation and fire co-ordination. Other improvements have included enhanced training for service personnel. 52 In 2021, Ukraine prioritised training its artillery units in fire damage and fire support and on their ability to conduct combined operations with other military units and special forces. 53 This focus on improving the quantitative and qualitative elements of its artillery has clearly paid off for the UAF. Ukrainian artillery, working in coordination with antiplatform weapon systems, had a decisive impact on the month-long battle for Kyiv at the start of the Russian invasion. 54 In this battle Ukrainian infantry fired anti-tank missiles at tanks and fighting vehicles at the vanguard of the Russian formations which blocked the Russian convoy allowing Ukrainian artillery to effectively target and attrite the 40-mile armoured column north of Kyiv. 55 Recognising the importance of artillery, Ukrainian fires have also been significantly augmented and enhanced since 2022 through western donations. 56 With the support of allies, in particular Bulgaria, Ukraine was also able to address the initial shortfall in munitions for Ukrainian artillery pieces due to Russian sabotage and supply problems. Ukraine's ammunition stocks at the start of the Russian invasion were very low with estimates suggesting that Ukraine only had enough ammunition for six weeks of high intensity warfighting. 57 Ukraine's focus on procuring anti-platform weapons, in particular anti-tank weapons, UAV's and special forces' equipment in the third stage of military reform have also proven important to its military success against Russian forces. 58 In light of the priority given to procuring these weapon systems, by February 2022, Ukraine had stockpiled a high number of anti-tank missiles such as the indigenously produced Stugna-P and the Korsar as well as a much smaller inventory of the shoulder-fired US made Javelin. In 2019 around 50 Stugna-P launchers, which are a Ukrainian man-portable anti-tank guided missile, were delivered to the Ukrainian military. 59 In the same year about the same amount of the Ukrainian built Korsar anti-tank missile, which is a high-precision older generation weapon capable of targeting any tank or self-propelled gun with at a distance of 2.5 km, were also delivered. In light of the importance of these weapon systems, in the weeks running up to the Russian invasion, there were plans to instruct Ukraine's Territorial Defence battalions in how to operate both the Stugna-P and Korsar anti-tank missile systems. 60 Since the invasion, these easily deployable anti-tank weapon systems have been successfully used by Ukrainian forces to ambush Russian forces and vehicles. 61 As part of its military reform process, the UAF also prioritised the procurement of new unmanned aerial and ground vehicles (UAVs or drones). UAVs have played an important role in the defence of Ukraine given their ability to track targets, shoot missiles, and enhance surveillance of the battlefield. In light of this priority of integrating new technology, Ukraine procured six Turkish made Bayraktar TB2 drones in 2018 and by the start of the conflict this had increased to 20. 62 Ukraine's use of the TB2 in the war builds on operational experience it gained during the conflict in the country's east. In October 2021, Ukrainian armed forces confirmed the use of the TB2 drone in the Donbas region during a counter-battery mission in a separatist-controlled area. The attack was reportedly successful, despite the presence of Russian electronic warfare and air defence assets. 63 In the Russian invasion the UAF have used unmanned UAV's, and artillery to halt Russian advances and mitigate its advantages in air power. The Bayraktar drones, in particular, have been widely recognised as important in the first phase of the war before the fighting became concentrated in eastern Ukraine. The Bayraktars, which were Ukraine's only armed UAV capability, have a range of up to three hundred kilometres, an endurance of up to twenty-seven hours, and can carry up to four laser-guided munitions. Bayraktars have been used to destroy Russian armoured assets, artillery, support vehicles, and ships since the full-scale invasion began. The Turkish-built drones have also been used by the UAF for reconnaissance, hunting for targets for Ukrainian ground troops. 64 Given the importance of UAVs, there has been a recognition that the UAF urgently needs access to modern equipment and to ensure a much wider dispersal of drone capabilities throughout the armed forces. 65 To facilitate this the Ukrainian Defence Minister Oleksii Reznikov confirmed in January 2023 that Ukraine would spend nearly $550 million on drones and that 16 supply deals had been signed with Ukrainian manufacturers. 66

Challenges of military reform
While Ukraine has made substantial progress in creating a military able to defend itself against the Russian invasion, deep-seated and inter-connected problems remain that will continue to hamper effective military reform and change in the future. These challenges include the lack of effective democratic oversight of the defence sector, endemic corruption and the need to reform Ukraine's state-owned defence industries so that they can produce the necessary equipment, at a price, quality, and quantity, required by the UAF. 67 Whilst the Ukrainian government has sought to bolster democratic control of and oversight of the military and security services, little real progress was made prior to the Russian invasion. Prior to the invasion key elements of democratic civil-military relations, such as meaningful civilian oversight of Ukraine's defence budget and procurement within the relevant ministries and parliamentary defence committees were clearly lacking. 68 In the majority of Ukraine's parliamentary committees, civilian security and military experts played little to no role in defence and security matters. 69 Further, hampering effective democratic oversight, over 90% of all of Ukraine's defence purchases are classified and the registry of defence supplies is also classified. 70 This lack of effective democratic oversight also exacerbates the problems with corruption in Ukraine's defence sector. 71 While corruption within Ukraine's defence sector has long been recognised as a problem, it has intensified since the start of the ATO. As Ukraine's defence budget has increased, so too has corruption as army chiefs and ministerial officials have been responsible for dispersing vast military budgets and overseeing real estate and arms stockpiles. 72 And, as a result, western allies have long expressed concern over where the humanitarian, financial and military aid provided to Kyiv ends up. 73 In light of growing western pressure to address endemic corruption, several specialised anti-corruption institutions were set up prior to the Russian invasion to investigate, prosecute, and adjudicate high-level corruption cases. However, these bodies have struggled to perform effectively their roles and stamp out corruption and there is concern as to how effective they will be when the conflict finally ends. 74 The ongoing conflict could however prove to be a turning point in Ukraine's long running battle with corruption. Ukraine's urgent need to continue to secure western economic and military support has recently proven to be an important motivator in encouraging the Ukrainian government to directly address allegations of corruption, particularly in the defence sector.
Perhaps the biggest challenge Ukraine has faced in building its armed forces, and one that will re-emerge after the conflict ends; however, is how to fund a large standing army, and, at the same time, effectively modernise its forces. Squaring this circle has been an ongoing challenge of military reform. The chronic underfunding of the Ukrainian military up to 2014 had a devasting effect on Ukraine's military capabilities. The UAF started the war in the east with obsolete and dated equipment, badly in need of modernising. 75 Although Ukraine's defence budget has risen significantly since 2014, the costs of modernising and upgrading Ukraine's military capabilities have been prohibitive, particularly given the high cost of retaining a large standing army. In 2014 for instance Ukraine defence budget represented an increase of 24.9% over the previous year and accounted for 1.78% of GDP, however, official figures show that more than 80% of the budget that year was spent on the maintenance of the UAF leaving little room for the procurement of new weapons. 76 This situation was little improved over the next few years. In 2015 and 2016 the further increase in defence spending, up from, 1.78% to 2.5% of GDP, did little to modernisation and develop the UAF; it merely covered the necessary costs associated with the conduct of military operations in the Donbas. 77 In 2020, Ukraine's defence budget reached an all-time high of roughly $6 billionor around 4% of the country's GDP, and again Ukraine spent a significant part of its budget maintaining its forces. 78 This enduring problem of how to move effectively from sustaining to developing Ukraine's armed forces has been further exacerbated by the urgent need to further increase the size of the UAF. By early 2022 Ukraine had 261,000 personnel, including 215,000 troops, with plans to further expand the UAF given the very real threat posed by the Russian Federation. 79 In Feb 2022, just weeks before the Russian invasion, President Volodymyr Zelensky signed a degree significantly increasing the size of the UAF by 100,000 personnel with the creation of up to 20 army brigades, signalling very clearly that the government's emphasis would continue to be on mass. 80 While this decision, in retrospect, can be seen as prudent, there has been concern that the focus on mass has been largely at the cost of modernising Ukraine's military capabilities. Months before the Russian invasion, Davyd Arakhamiyam, head of the Servant of the People's faction in the Ukrainian parliament, called for a reduction in UAF numbers claiming that Ukraine could not afford to pay for such a large force from the existing defence budget and that this policy was hampering the construction of a mobile and well-equipped Ukrainian force. 81 He went on to point out that there are not enough funds to rearm the Army, buy new things, new weapons, and new technologies. In essence, there was a recognition amongst many commentators and politicians in Ukraine that the retention of a large force would ultimately delay the possibility of the high-tech rearmament of the UAF. Up until the Russian invasion, the Ukrainian government was spending more than 70% of the defence budget on personnel, leaving about one fifth, estimated to be about one billion dollars, for new and upgraded equipment. 82 According to experts, ideally a defence budget would be divided into three roughly equal elements: with a state spending a third of its defence budget on personnel; a third on the purchase and modernisation of weapon systems; and the last third paying for military operations and maintenance. 83 Most Western militaries, however, even those fielding relative small standing armies, as against Ukraine's large force, have also struggled to balance defence spending in this way. 84 Even if Ukraine was in a position to reduce the size of its military in the near future, which appears highly unlikely, it will still struggle, however, to build a modern military. In order to effectively modernise the UAF, Ukraine would need to significantly increase its defence budgetestimates suggest it would need to increase fivefold. 85 The reasons for this are multifaceted. Ukraine needs to upgrade its weapon systems across the board. Even before the Russian invasion, the UAF had a very long list of requirements. Ukraine's former Commander in Chief, Ruslan Khomchak, had stated in 2020 that the UAF needed to procure small arms, artillery systems, anti-missile systems, new armoured personnel carriers, modernised tanks, reconnaissance assets for the navy, anti-sniper systems, parachutes and modern means of communications and electronic warfare and ships for the navy. 86 While some of these military capabilities can, at least in theory be developed domestically, this is not without its problems. UKROBORONPROM, which, up until 2021, when it was turned into a joint stock company, managed the enterprises of Ukraine's military-industrial complex, and has been wracked by serious allocations of corruption and accused of not producing either the quality or quantity of armaments required by the UAF. 87 Many of the capabilities needed by the UAF will therefore need to be "bought off the shelf" putting considerable pressure on Ukraine's limited procurement budget. For instance, depending on which air platforms Ukraine purchases, the cost of upgrading its tactical aircraft alone is likely to run into billions of dollars; more than the whole of Ukraine's procurement budget for 2021. 88 Given the need to rebuild Ukraine after the Russian invasion, a fivefold increase in the defence budget is improbable, and certainly unachievable in the medium term.

Conclusion
Although Ukraine's third wave of military reform hasn't been without its problems, some of them long-standing, it has created some of the enabling conditions for Ukraine's success on the battlefield. Ukraine has made real progress in a number of key areas, which have proved to be important in the fight against Russia, including the development of an effective command and control system, developing an NCO Corps and SF's as well as having some clear priorities for its defence procurement. The adoption of a hybrid transformation model of military reform in 2016 with a focus on mass, but also, on building a western style NATO interoperable and trained military has forced Ukrainian decision makers to make some tough, but clearly astute choices. 89 Ukraine could not afford either financially or politically to return to the full transformational model of military reform discussed earlier. Instead, faced with the conflict in the east Ukraine had had little option but to build and sustain a costly large standing army and focus what is left of its defence spending in key areas. After the conflict ends, Ukraine will continue to have to make some hard choices. To protect its security, Ukraine will no doubt have to retain a large standing army for the foreseeable future. As Ukraine's defence budget is unlikely to increase significantly and given the urgent need to rebuild Ukrainian cities after the war, the enduring struggle to balance the requirement for mass against modernisation will continue to plague Ukraine's military reform. While continued western military and economic assistance is likely to offset some of these challenges, at least in the short term, it will not resolve the heart of the problemthe inherent unsuitability of the transformation model for many states who face an existential threat, including Ukraine.