3.1 China and Russia's perceptions of the US's Pivot to Asia

China recognized the US Pivot to Asia strategy as an expansion of the US encirclement of China. That is, China considered the US rebalancing policy as a blatant check on its rise, and it did not hide its concerns over the strengthening of the US–Japan alliance, expansion of cooperation with Southeast Asian countries, and intervention in Taiwan. In fact, since 2010, China has experienced the US check across various areas, including territorial conflicts with Japan, the US intervention in Taiwan, conflicts with the USA over trade and tariff, and others.

This perception of threat by China was well illustrated in China's 2013 Defense White Paper; pointing out that the geopolitics in the region was undergoing profound changes as the USA rebalanced its security strategies (The State Council Information Office of the PRC, 2013), China recognized the changes in the US security strategies as a threat to its interests. The increased perception of threat of China by the USA was also reflected in China's foreign strategy. Before 2012, China's foreign strategy focused on ‘peaceful development’ based on Taoguangyanghui (韜光養晦) of Deng Xiaoping. However, when the Xi Jinping administration was about to officially launch, the emphasis on ‘core interests’ started becoming pronounced. In November 2012, the report of the 18th National Congress of the Chinese Communist Party stated that it would maintain its foreign policy stance of ‘peaceful development’ but, at the same time, it emphasized that it would not abandon China's legitimate rights and interests nor sacrifice the country's ‘core interests’ (Hu, Reference Hu2012; Renmin ribao, 2012).

Chinese scholars have openly expressed their vigilance over the US rebalancing policy in Asia. Many scholars judged the rebalancing policy in Asia as an excessive check on China and feared that increased US involvement would weaken China's regional influence in the future (Fan, Reference Fan2012; Yuan, Reference Yuan2012; Wang and Ling, Reference Wang and Ling2013). There was even a claim called for the abolition of existing policies of non-alignment and the revival of alliance policies to respond to the threats posed by the USA. In particular, as a practical way to prepare for the expansion of US checks, the alliance with Russia has drawn attention. The logic was to respond to the US checks through the Sino–Russian alliance because the two countries share common factors for cooperation such as sharing historical ideology, checks on Western countries, territorial disputes with Japan, and checks on the expansion of the US–Japan alliance. They projected that the reality of accelerating pressure on China because of the US Pivot to Asia is inevitable and that China will eventually be isolated if the situation continues. If there is no alliance, China will inevitably be at a disadvantage in the midst of future changes in the international order and, therefore, it should actively increase the number of allies (Yan, Reference Yan2012a: 21; Wu, Reference Wu2012; Shi, Reference Shi2013: 1–3). It has even been argued that China should actively involve in South Korea and the Philippines, which have weak connections among the existing US allies or adopt a traditional military alliance with Russia with the aim of responding to the US threats. In addition, it was also argued that China should bring those 12 neighboring countries in the alliance established around the Shanghai Cooperation Organization (SCO) such as Pakistan, Bangladesh, Sri Lanka, Laos, Myanmar, Cambodia, and North Korea – which share the common factor that they are under international pressure from the USA – into China's alliance system to ensure their security (Yan, Reference Yan2012b: 21–25; Yan, Reference Yan2013: 194).

Although the US rebalancing toward Asia was not perceived as a direct or serious threat by Russia, as China perceived, Moscow also expressed its concerns. In the early 2010s, Russia recognized the expansion of the North Atlantic Treaty Organization (NATO) and the establishment of the MD system as a product of US unilateralism policy and a priority threat to its national security. Then Prime Minister Vladimir Putin, who was facing the 2012 presidential elections, criticized NATO expansion and Europe's plan to build the MD system as the ‘stereotypes of a block-based mentality’ in an article published in Moskovskiye Novosti on February 27, while referring to the MD system as an attempt to destroy the strategic balance by damaging Russia's strategic nuclear deterrence (Putin, Reference Putin2012b).

Under these circumstances, US Pivot to Asia was another national security threat on Russia's western border, following its eastern border. First, due to the deterioration of the US–Russia relations, Russia perceived US Pivot to Asia as a threat to jointly respond to, with China. Relations between the two countries, which continued to deteriorate from the mid-2000s to the Russo-Georgian War in August 2008, improved dramatically by using the term ‘reset’ in 2009. However, when the USA unilaterally proceeded with expanding NATO and establishing the MD system in Europe despite opposition from Russia, and the relations between the two countries worsened again, Russia's long-standing habit of pursuing a geopolitical balance was revived (Lo, Reference Lo2015: 142). The ‘Military Doctrine of the Russian Federation,’ revised in February 2010, has defined: (1) ‘attempts to destabilize the situation in individual states and regions and to undermine strategic stability’; (2) ‘deployment (buildup) of troop contingents of foreign states (groups of states) on the territories of states contiguous with the Russian Federation and its allies and also in adjacent waters as basic external military risks’ (Russian Federation, 2010). The ‘Foreign Policy Concept of the Russian Federation,’ revised in February 2013, clarified the perception of threats to ‘Pivot to Asia,’ claiming that instability in international relations is growing due to Western countries' desire to preserve their dominant position at a time when the global power and development potential is shifting to the Asia-Pacific region (Russian Federation, 2013). Furthermore, the experts on Northeast-Asian affairs in Russia pointed out that in Hillary Clinton's article in the journal Foreign Policy in November 2011 (Clinton, Reference Clinton2011), there was no mention of cooperation with Russia and the experts argued that the USA is ignoring Russia's interests in the Asia-Pacific region (Amirov et al., Reference Amirov, Vorontsov, Voskresenskiy, Dubinin, Zevelev, Kanayev, Lunev, Mosyakov, Orlov, Petelin, Stapran, Sumskiy, Terekhov, Tulinov and Chufrin2012: 100) and trying to strengthen its existing alliance and create a Northeast-Asian version of NATO (Molchanov, Reference Molchanov2019). Therefore, while the US rebalancing strategy toward Asia did not present an immediate threat to Russia, it was recognized as a future strategy to encircle Russia, given that the coalition formed against China could also be used against Russia as coalitions rarely identify the specific threats against which they are formed to target. As a result, Russia had no choice but to share its perception of the threat by Pivot to Asia with China in Northeast Asia.

Second, Russia perceived US Pivot to Asia as a threat to the development in the Far East. Russia began to pursue development in the Far East through cooperation with countries in the Asia-Pacific region in the early 2010s. In this regard, the ‘Foreign Policy Concept of the Russian Federation,’ revised in February 2013, noted that ‘Russia is interested in using the possibilities offered by the Asia-Pacific region to implement programs meant to boost Siberian and Far Eastern economy,’ stressing that the overall improvement of political and security environment in the Asia-Pacific region is fundamental importance for Russia (Russian Federation, 2013). Thus, US Pivot to Asia was seen as a clear threat to Russia's interests in that it intensified strategic instability in the neighboring areas, creating a negative external environment for development in the Far East, and interrupting Russia's expansion of economic cooperation with the countries in the Asia-Pacific region by attracting the countries to a US-led security and cooperation architecture.

Based on these concerns, Russia has begun to emphasize its commitment to cooperation with China in full measure. In an article published in Moskovsky Novosti in 2012, then Prime Minister Putin referred to China as a partner who shares a vision of a new international order, arguing that Russia and China should work together to address regional and global challenges (Putin, Reference Putin2012b). Furthermore, in another article published in Renmin Ribao in 2012, before attending the SCO summit, Putin emphasized, targeting the USA, that ‘We consider any unilateral attempt by a third country to intervene in Asia to be unproductive’ (Putin, Reference Putin2012a).

In the ‘Foreign Policy Concept of the Russian Federation,’ revised in February 2013, he also stated, ‘Russia will continue to strengthen its comprehensive, equal and trusted partnerships, and strategic collaboration with China, and actively develop cooperation with China in all areas,’ vowing to strengthen the partnership of the two countries against the challenges and threats of the USA (Russian Federation, 2013).

3.2 The growing China–Russia military engagement

With this growing perception of threats from the USA, China and Russia stepped up their defense and strategic cooperation. One remarkable indicator of enhanced bilateral cooperation was the development of their joint military exercises since the early 2010s. As Sergei Shoigu, then Russian Minister of Defense, points out, joint military exercises are the most important issue in China–Russia strategic cooperation, and contribute to their joint preparedness against common threats (Meick, Reference Meick2017: 6). While their first bilateral military drill started in 2003, and they have also participated in multilateral exercises under SCO since the mid-2000s, China and Russia have expanded the size and geographical reach of bilateral exercises, upgraded the level of integration between the two militaries, and lifted the level of weapons for their bilateral exercises, specifically since the early 2010s, when the USA discussed its Pivot to Asia strategy (Meick, Reference Meick2017: 8). Moreover, they took the significant step of deepening their defense engagement by launching a new bilateral naval exercise, the Joint Sea, in 2012 (Korolev, Reference Korolev2018: 35). Specifically, for the first Joint Sea exercise held in the Yellow Sea, both Beijing and Moscow sent the largest-ever naval forces: the total number of forces participating was 10,000; China deployed 16 warships, two submarines, 13 aircraft, and five helicopters, while Russia sent four warships, three supply ships, four helicopters, and naval task forces (BBC, 2012). Moreover, given that the first Joint Sea exercise was launched a few months after the Obama administration officially clarified its Pivot to Asia strategy, the timing indicates that China and Russia recognized the need to prepare together for potential intimidation from the USA, and to expedite their defense ties.

This newly launched naval drill was neither a one-time event nor a showcase simply demonstrating their power. Since 2012, both countries have held a Joint Sea exercise on a yearly basis, continually expanding its level of complexity and sophistication. For the first two exercises, held in 2012 and 2013, respectively, the Chinese Navy deployed the largest-ever military force in a China-foreign country joint exercise (BBC, 2013). The exercises also covered comprehensive joint trainings. During the first and second Joint Sea exercises, the two navies conducted various drills, such as anti-submarine warfare, joint maritime air defense, naval logistics, and island-seizing trainings, aimed at improving joint mission capabilities during both peace and war time, coordination capabilities, and interoperability (Korolev, Reference Korolev2018: 35).

In addition, it was argued that in many ways the second Joint Sea exercise was more significant and comprehensive than the first drill (Weitz, Reference Weitz2015: 20). Most of all, through the second drill, China and Russia sent a resolute signal to the international community that they would support each other on sensitive issues on the international stage, considering that the exercise took place around the East Sea/Sea of Japan while tensions over the nearby East China Sea were mounting. By deploying important naval assets to neighboring waters and conducting naval drills with live-firing, Beijing and Moscow showed together that they would deal firmly with any attempts to infringe on their interests. Also, for the second drill, although the number of military forces deployed were fewer than in the first, China sent its most advanced naval assets, such as an up-to-date guided-missile destroyer equipped with Aegis-type radar, and anti-submarine warfare frigates (Weitz, Reference Weitz2015: 21). The inauguration of Joint Sea thus demonstrates China and Russia's significant efforts to deepen and widen their mutual defense cooperation.

Another indicator of the consolidation of the China–Russia defense engagement is meaningful initiatives for joint arms development since 2012. Specifically, between 2012 and 2013, several meaningful and important agreements and initiatives were signed, strengthening the foundation for joint development of weapons and defense equipment. In 2012, for instance, China and Russia discussed a framework for propelling co-production of four LADA-class diesel electric submarines; in 2013, after the Summit, Beijing and Moscow officially signed an agreement for the joint production of these submarines (Meick, Reference Meick2017: 16). With this agreement, they could enhance their industrial cooperation on mutual defense, and China was offered core technology and knowhow to build a quieter and more advanced diesel electric submarine than the KILO-class submarine, which at that time was the Chinese Navy's most capable diesel submarine in service (Meick, Reference Meick2017: 16).

Furthermore, since 2012, Russia has provided China with access to some of its advanced weaponry. Of course, while Russia had been the biggest arms supplier to China in the past, it had been reluctant to offer China its up-to-date weapon system, mainly due to concern that China could copy its technology (Schwartz, Reference Schwartz2015: 38–39). However, around 2012, China was able to obtain the most sophisticated weapon technology from Russia applicable to engines for China's first aircraft carrier, Liaoning, and to its A2/AD systems (Carlson, Reference Carlson, Thränert and Zapfe2018a: 35). It should also be noted that, while a series of arrangements of defense research and development (R&D) between China and Russia was initiated in the 2000s, the bilateral R&D for weapons began to include cutting-edge and advanced military technology only after the early 2010s (Meick, Reference Meick2017: 15).

Given the timing of these incremental shifts, it can be argued that China's and Russia's shared perception of threat from the USA, which was derived from the US Pivot to Asia strategy, contributed to the stepping up of the China–Russia defense ties. After the meeting in 2013, both Sergei Shoigu, the Russian Defense Minister, and Fang Fenghui, then Chief of the General Staff of China, called for enhanced China–Russia coordination in the context of challenges threatening regional and international peace (China Daily, 2013). Although they did not explicitly name the USA, they arguably recognized that it was taking active measures to contain their influences or prevent them from achieving regional interests, and thus China and Russia made greater efforts to advance their security, defense, and military engagement.

4.1 China and Russia's perception of the Ukraine crisis and the US-led sanctions

This event generated China and Russia's additional concerns and aggravated their perception of threat from the USA. At first, China's stance on the Ukrainian crisis was ambiguous. While cooperation with Russia became important to form an opposition front against the course of intensifying checks on China because of the US rebalancing policy in Asia, it was also necessary to refrain from expanding the inevitable competition with the USA in the international community by officially supporting Russia. Therefore, at a UN Security Council meeting, China did not vote either for or against but abstained from voting on the resolution of the referendum on Russia's annexation of the Crimean Republic. Regarding the issue of the Crimean Peninsula, the Chinese Foreign Ministry only provided a theoretical stance, suggesting that ‘the means to a political settlement should be explored by establishing an international coordinating mechanism involving all relevant countries’ (Ministry of Foreign Affairs of the PRC, 2014a).

However, China's ambiguous stance turned somewhat favorable to Russia when sanctions against Russia imposed by the USA and Europe tightened. At that time, China seemed to have seriously agonized over the stability of its territorial integration. In China, there have been protests in Hong Kong and Macau over democratic reform in connection with direct elections in special administrative regions, and thousands of people have carried out online voting on the issue. The Communist Party of China ignored their demands, which eventually led to Hong Kong's so-called Umbrella Revolution in September 2014 (SCMP, 2014). The Communist Party of China considered a series of demonstrations as an attempt of West-backed color revolution. China defined Hong Kong protests as an internal issue for China and an issue of territorial integration, and it was strongly wary of the USA and others intervening or linking them to Ukrainian issues. These concerns over the US and Western involvement have intensified anti-Western rhetoric and pro-Russian views since the Ukrainian crisis. In other words, China shared the threat perception with Russia in that the strong US and Western checks on Russia's territorial integration are an imminent future threat to China as well.

China's strong opposition to Western intervention was confirmed clearly at the CICA meeting in May 2014, when Russia's annexation of a Crimean Peninsula was decided. At the meeting, Chinese President Xi Jinping declared the New Asian security concept (亚洲新安全观) (Xi, Reference Xi2014). This illustrates that China began to have resolute will to hedge America's rebalancing to Asia. Through the New Asian security concept, President Xi underscored that Asia should solve its security problems (Navarro, Reference Navarro2014). What is noteworthy is that Putin attended the meeting, and Putin also responded to Xi's proposal, saying that the Asia-Pacific region needs a security organization with equal cooperation principles and openness. Furthermore, at the Sino–Russian summit that took place along with the meeting, the two leaders shared a sense of threat by the West by clarifying their opposition to international sanctions against Russia after the crisis of the Crimean Peninsula and by opposing internal intervention and calling for an end to unilateral sanctions against the USA and Europe (Remin ribao, 2014).

The diplomatic and military establishment in China continued to perceive the USA and the West as a threat in relation to the Ukrainian crisis, and China emphasized cooperation with Russia to overcome this threat. For example, the Chinese Foreign Ministry spokesman stressed, ‘China opposes Western sanctions against Russia, and China will continue its strategic partnership with Russia regardless of how the international environment changes’ (Ministry of Foreign Affairs of the PRC, 2014b). In addition, in his interview with Russian medias, one Chinese high-ranking diplomat articulated that the Chinese government understood that Russia is confronting threats and challenges from the US-led Western coalition, and said that ‘China categorically stands against some undermining other countries’ security in order to defend so-called “total security”’ (TASS, 2014). Meanwhile, perceiving the Ukraine crisis as a new effort by the West to intervene, one Chinese active-duty general claimed that such an intervention would invite a new confrontation between the West and non-West, which would eventually cause future concerns for China (Qianjiang wanbao, 2014).

The 2014 Ukrainian crisis and Western sanctions against Russia also led to a significant escalation of Russia's sense of crisis. After signing the Treaty on Accession of the Republic Crimea on 18 March 2014, Russia's awareness of threats could be identified in President Putin's speech as follows (Putin, Reference Putin2014): ‘First, the treaty perceived the “Ukrainian crisis” as an extension of the US unilateralist policy, which continued to bomb and intervene in the Yugoslavia, involve itself in Afghanistan, Iraq, and Libya, Color Revolution, and so on. Second, the Ukrainian crisis was perceived as a product of containment policies against Russia, including the expansion of NATO, the establishment of the MD system, and economic sanctions.’ In particular, Putin argued, ‘The notorious containment policy executed against Russia in the 18th, 19th, and 20th centuries continues today.’ In other words, Russia recognized the Ukrainian crisis – an extension of the US unilateralist policy and a product of the containment policy against Russia – as a serious threat to its national security.

Meanwhile, the ‘Military Doctrine of the Russian Federation,’ revised in December 2014, also defined the results of the Ukrainian crisis, which is ‘the establishment of a system that runs policies to threaten Russia's interests in neighboring countries,’ as a main external military risk (Russian Federation, 2014). Russia has criticized the Color Revolution in Georgia and Ukraine, but the previous ‘military doctrines’ did not define it as a military risk. In addition, the ‘National Security Strategy of the Russian Federation,’ revised in December 2015, interpreted the ‘Ukraine crisis’ as the result of Western support for pro-Western power to disrupt Russian-led Eurasian regional integration and pointed out economic sanctions against Russia as the factor of destabilizing the international economic system (Russian Federation, 2015).

Based on this sense of crisis, Russia felt the need to further strengthen its relationship with China. The ‘National Security Strategy of the Russian Federation,’ revised in December 2015 defined military security challenges in the Asia-Pacific region for the first time, particularly emphasizing ‘the development of comprehensive partnership and strategic cooperative relations with China’ and ‘the establishment of regional stability and security mechanisms based on non-bloc principles’ (Russian Federation, 2015).

Although China's and Russia's security fears regarding the US Pivot to Asia still had not dissipated, the second critical juncture further raised their perception of the USA as a threat. From Beijing's perspective, the second critical juncture gave rise to another concern; while the US rebalancing strategy was regarded as an effort to contain China, the Ukraine crisis was deemed a potential threat to Chinese national and territorial integration. Meanwhile, while worrying that the US rebalancing strategy toward Asia would result in an unfavorable strategic environment in the eastern part of its territory, Moscow regarded the Ukraine crisis as a serious security threat from the USA.

4.2 Stepping up of the China–Russia engagement

With such growing threat perceptions, after the Ukraine Crisis and the US-led pressures against Russia, the China–Russia strategic relationship stepped up a gear. In 2015, one important mechanism for the bilateral defense cooperation was initiated: the China–Russia Northeast Asia Security Dialogue (NASD). It was claimed that the NASD laid a ‘new platform for regional security consultation’ between these two countries, aimed at jointly dealing with common security threats and contingencies in this region (Korolev, Reference Korolev2019: 238). In this dialogue held once every 2–3 months, the Chinese and Russian delegates, including various ranks of diplomats and military personnel, held a series of meetings on a tight schedule, discussing various security-related issues (Korolev, Reference Korolev2019: 238–240). Specifically, after analyzing the stated purposes and agendas of such meetings, Korolev (Reference Korolev2019) claims that both China and Russia had growing concerns over the US factor regarding international security circumstances and recognized the necessity of collaboration.

The development of a China–Russia joint drill was another important indicator of these enhanced bilateral strategic ties after 2014. Specifically, the Joint Sea held in 2015 was the first exercise held outside adjacent waters of China or Russia (Meick, Reference Meick2017: 9). The Joint Sea 2015 was divided into two phases, and the first held around the Mediterranean Sea, indicating that their joint naval drill had expanded beyond their yards. That is, considering that the first two Joint Sea exercises were held in the waters close to the East Sea/Sea of Japan and near Vladivostok, the Joint Sea 2015 showed not only that their geographical reach had significantly expanded, but also that both countries had sufficient capabilities to coordinate on the open seas (Korolev, Reference Korolev2019: 244).

In addition, the size of this exercise was also increased. Specifically in terms of the number of surface ships, China and Russia sent the largest number of surface warships for the second phase of the Joint Sea 2015; Russia sent 16 surface vessels, 12 maritime attack helicopters, and nine amphibious vehicles, while China sent seven surface warships, five fixed-wing aircraft, five helicopters, and 21 amphibious vehicles (USNI News, 2015; Meick, Reference Meick2017: 10). This exercise, for the first time, covered amphibious assault training, demonstrating the improved and sophisticated coordination capabilities between the two navies.

The Joint Sea exercise held in 2015 was regarded not only as a ‘geographical game changer,’ but also as a cornerstone of China–Russia defense ties (Korolev, Reference Korolev2019: 244). It can be argued that both countries' shared concerns over the growing tough stance by the USA against them motivated this development in the China–Russia defense engagement. In the announcement of a plan for the Joint Sea 2015, indeed, Sergei Shoigu stated that ‘the US factor played a pivotal role in causing an increase in China-Russia joint exercises around the world, including the Pacific’ (USNI News, 2015).

The high-level military-to-military meetings between them also showed an incremental trajectory in their military engagement. As seen in Figure 1, since 2012, the total number of meetings has steadily increased. Also notable is the fact that the proportion of the higher-ranking meetings grew remarkably between 2014 and 2015; during this period, the top-level and senior-level meetings accounted for more than 80%, while between 2007 and 2009, these higher-level meetings accounted for less than 50%. Moreover, in 2015, the Russian minister of defense and Chinese vice chairman of the CMC met five times, which was the most frequent in a decade. This indicates that China and Russia have brought up more comprehensive and sophisticated defense-related agendas since the mid-2010s.

Figure 1. High-level military-to-military meetings.

Note: the Department-level meetings include ‘those involving deputy commanders of the services and assistants to the chief of the general staff department’; the Deputy-level meetings include ‘those involving a deputy chief of the general staff, and military region (China) or military district (Russia) commanders’; the Senior-level meetings include ‘those involving Russian deputy defense ministers, Chinese Central Military Commission (CMC) members, and service commanders’; and the Top-level meetings include ‘Russia's minister of defense and China's vice chairman of the CMC.’

Source: Meick (Reference Meick2017: 19).

The arms transfer and joint development for weapons between these two countries further evolved even compared to the first critical juncture period. Most of all, after the Ukraine Crisis, there was a milestone in the bilateral defense relationship: Russia offered its top-flight weapons to China. Specifically, in 2014, China and Russia agreed that Russia would eventually sell its two top-flight weapons, its S-400 air defense system and 24 Su-35 fight jets (Carlson, Reference Carlson, Thränert and Zapfe2018a: 35–36). Although both countries had gradually traded cutting-edge weapons and engaged in joint development for defense technology since the early 2010s, Moscow had still been reluctant to agree to sell these two weapon systems to China. Indeed, while they began a series of negotiations for transferring S-400 and Su-35 fighters in the early 2010s, Russia did not settle the agreement with China until the last moment. However, experiencing the Ukraine Crisis and confronting the US pressures, Russia changed its attitude over this issue. Most of all, after these events, Russia acknowledged that its partnership with China was one of the most essential agendas and sought to reinforce their strategic ties a step further by selling China its two top-flight weapons (Carlson, Reference Carlson, Thränert and Zapfe2018a: 37). In addition, after a thorough investigation, the Russian government concluded that it would require quite a long time for China to copy its S-400 and fifth-generation fighters, which alleviated Russian concerns over China's attempts to copy and reverse engineer (Meick, Reference Meick2017; Carlson, Reference Carlson, Thränert and Zapfe2018a: 37).Footnote ² Thus, in order to deal with any potential collision with the USA and its allies, Russia, putting aside its concerns over copy-related issues, decided to provide its most top-flight weapons to China. By doing so, both countries were able to improve their aggregate capabilities to deal with their shared perceived threat.

Furthermore, bilateral cooperation on the defense industry and technology further intensified between 2014 and 2015. Specifically, compared to the first critical juncture period, their joint arms development during the second critical juncture marked several evolving features. First, both countries signed bilateral arrangements for R&D for more frequent joint arms development, and the cooperation fields became more comprehensive (Meick, Reference Meick2017; Korolev, Reference Korolev2019). For instance, in November 2014, they signed four agreements enabling their air-defense firms to engage in R&D covering fixed-wing plane and helicopter manufacture, and engine development; in May 2015, they reached a deal to jointly develop a next-generation heavy-lift helicopters, which led to expansion of cooperation areas and promotion of R&D between them (Korolev, Reference Korolev2019: 241–242). Second, between 2014 and 2015, bilateral R&D began to cover state-of-the-art defense technology, such as aerospace science and information (Meick, Reference Meick2017). Indeed, China and Russia initiated cooperation in earnest in the space area around 2014. Between 2014 and 2015, they concluded a bargain to develop a satellite navigation system as well as to cooperate for on various space-related technology (Korolev, Reference Korolev2019: 241). Finally, bilateral cooperation for arms development shifted from one-way to reciprocal cooperation. That is, in terms of arms development, while in the past Russia was generally the supplier and China the recipient, China expanded its role as a co-developer. Since the mid-2010s, China began to offer various resources, information, and aids to Russia: for instance, after the West-Russia tension intensified in 2014, China played a larger role in developing space program, drone technology, and engines for warships (Korolev, Reference Korolev2019: 242). Since 2014, in terms of joint arms and technology development, they have become indispensable partners.

The Ukraine crisis and the US policy against Russia led the latter to perceive that a US-led network was pressuring Russia in order to bring Moscow into submission. From the Russian perspective, the USA and the West were trying to disturb Russia's important national interests and integrity. China, although to a lesser degree, also recognized that the USA was trying unilaterally to intervene and defeat its competitors. After the Ukraine Crisis in 2014, therefore, China and Russia took further steps to enhance their defense relations.

5.1 China and Russia's perception of the THAAD deployment

The deployment of the THAAD has made China aware of the US threat even more clearly. China defined the THAAD system as a check on China by the USA and a clear threat to its security interests. Chinese Foreign Ministry has expressed its continued and clear opposition to THAAD, saying it violates China's security interests and regional peace and stability. According to a study analyzing the Chinese Foreign Ministry briefing on THAAD, China has highlighted its national security interests or strategic security interests in its comments on THAAD deployment. Specifically, after the THAAD deployment was decided, the perception of strategic threats from THAAD deployment has increased as the frequency of expression of strategic security interests rather than that of security interests has increased (Lee, Reference Lee2017: 17–22).

In particular, China was officially concerned that the X-band radar of the THAAD system could be monitored beyond North Korea to the middle of the Chinese continent (Ministry of Foreign Affairs of PRC, 2015). China's major media and experts also argued that the range of X-band radar could cover China and the Asian region, which effectively incapacitates missile bases off China's eastern coast and that missile test information across China would be collected during a peaceful period (Wu, Reference Wu2014: 341–358; Remin ribao, 2016; Wang and Xing, Reference Wang and Xing2016: 49–53).

China perceived South Korea's THAAD deployment as an expansion of the US missile defense system to keep China in check rather than as a means to keep North Korea in check. China believes that since THAAD is ineffective in terms of deterrence against North Korea's missile threats, the actual function is to inform the US missile defense system through the THAAD radar system and to gather accurate information on China's intercontinental ballistic missiles through the radar and linkage of existing Alaska Air Force bases. For this reason, it is argued that South Korea's THAAD deployment is a threat to China's military strategy in Northeast Asia and an infringement on its strategic security interests. China has long been working with Russia to declare strong opposition to the US's missile defense initiative. China and Russia said they strongly oppose the US missile defense plan because it is aimed at pursuing a one-sided military and security supremacy, which would have serious side effects on the security of Russia and China (Nangfang ribao, 2012). In particular, it was also concerned that the US missile defense system is directly linked to the Aegis Ashore missile defense system in Eastern Europe, which allows the USA to complete the construction of its global missile defense system (Li, Reference Li2016: 51–52). This is why China perceived the THAAD deployment as a joint security threat to China and Russia.

Moreover, the US decision to deploy THAAD has deepened China's security concerns since it was a reinforcement of the US-led alliance system as a part of the US rebalancing policy in Asia. In fact, since the US Pivot to Asia in 2010, countries such as Japan, Australia, the Philippines, and Vietnam have expanded their bandwagon strategies toward the USA. This bandwagoning eventually caused conflicts with China over territorial, territorial waters, and trade issues. Under these circumstances, South Korea's decision to accept THAAD was interpreted as bandwagoning to strengthen the US security frame against China (Jiefang junbao, 2016). South Korea's acceptance also meant that China's diplomatic strategy to weaken the US–South Korea alliance through strengthening ties between South Korea and China had failed, while raising concerns over strengthening of US–Japan–South Korea alliance to keep China in check in the future.

This threat perception of China eventually forced itself to prepare strong countermeasures against threats and checks by the USA. Even in the Chinese media and others, there has been an increase in explicit requests that the Chinese government should respond strongly to US threats. The Chinese State-run media Huanqiu Shibao argued that ‘as the purpose of THAAD is to curb China and Russia's military power, China's nuclear threats should be strengthened to deal with potential threats from the THAAD deployment’; it also declared that ‘the US has broken the strategic balance by deploying a missile defense system at China's doorstep,’ and ‘in order to regain the strategic balance, it should establish a full-scale strategic partnership with Russia and respond to the threats by the US’ (Huanqiu Shibao, 2017). Other claims have been made to deepen missile technology cooperation with Russia to defend the common security interests or to emphasize the need for military solidarity (Renminwang, 2016; Xie, Reference Xie2017). As such, China perceived the deployment of THAAD as a US threat to expand checks on its country and, in response, it was necessary for China to further strengthen its cooperation with Russia, which shares security threats regarding the USA.

The deployment of THAAD also sounded an alarm bell for Russia. The establishment of the global MD system that the USA is pushing for has been Russia's most critical external threat since the early 2010s. The USA claims that the purpose of the THAAD deployment was not to keep Russia (and China) in check, but Russia interpreted it as an attempt to strengthen US unilateralist policies at the global level by destroying the strategic balance between the two countries, which was secured by the 1972 Anti-Ballistic Missile Treaty; thus, Russia saw the USA as gaining a strategic advantage. The ‘National Security Strategy of the Russian Federation,’ revised in December 2015, claimed that ‘The opportunities for maintaining global and regional stability are shrinking significantly with the siting in Europe, the Asia-Pacific region, and the Near East of components of the US missile defense system in the conditions of the practical implementation of the ‘global strike’ concept and the deployment of strategic non-nuclear precision weapon systems’ (Russian Federation, 2015). In addition, the ‘Foreign Policy Concept of the Russian Federation’ revised in November 2016 also emphasized the willingness to actively respond to the establishment of the US global MD system by saying, ‘Russia views the establishment of the US global MD system as a threat to national security and has the right to adopt appropriate countermeasures’ (Russian Federation, 2016). After all, although Russia's concern about the THAAD deployment by the USA may not have been as serious as China's concerns, considering the geographical location of the THAAD, the deployment complicated Moscow's strategic calculations about the future because expanding deployments in Korea could also occur in Europe (as evidenced by the deployment to Romania).

Against this backdrop, Russia could not easily accept the US and South Korea's claim that the decision to deploy THAAD in South Korea, in July 2016, was aimed at responding to the threats by North Korea, and rather perceived it as a measure to build the US global MD in the Asia-Pacific region following Europe. On 8 July 2016, through the Russian Foreign Ministry's statement on the decision to deploy THAAD in South Korea, the Ministry expressed a ‘very serious concern.’ The statement described the deployment of THAAD in South Korea as the Asian-Pacific segment of the US global MD system that the USA is building with its allies, and criticized that such actions would not only have a negative impact on global strategic stability, but they are also a ‘threat that can sharpen regional tensions’ and ‘creating new difficulties in solving complex problems on the Korean Peninsula, including the denuclearization challenges’ (Ministry of Foreign Affairs of the Russian Federation, 2016a, 2016d). In addition, on the same day, Deputy Foreign Minister Igor V. Morgulov delivered Russia's ‘very serious concerns’ in consultation with South Korean Vice Foreign Minister Kim Hyung-jin (Ministry of Foreign Affairs of the Russian Federation, 2016b).

In response to the claim that the deployment of THAAD in South Korea had a ‘defensive nature’ only for the containment of North Korea's missile threats, Russian Ambassador to South Korea Alexander A. Timonin also said, in an interview with TASS, that Russia refuted it as an extension of the US efforts to build a new regional segment of global MD in Northeast Asia near the Russian border, and argued that the basic goal of the US global MD system is to reduce the efficiency of Russia's missile potential as much as possible, which is a direct threat to Russian security. He also added that the deployment of THAAD in South Korea has clearly exceeded the scope of the task of curbing the ‘threats by North Korea,’ as it could lead to the erosion of the existing strategic balance and damage Russia's continuous efforts to strengthen mutual trust, partnership, and cooperation in Northeast Asia (Ministry of Foreign Affairs of the Russian Federation, 2017).

In the fifth round of the Russia–China Dialogue on Security in Northeastern Asia, held in 2016, the two countries expressed concern about the desire of the USA and some other countries to use North Korea's nuclear and missile programs to change the strategic balance in Northeast Asia. In this context, they highlighted the negative impact of the decision to deploy THAAD in South Korea (Ministry of Foreign Affairs of the Russian Federation, 2016c). The ‘Foreign Policy Concept of the Russian Federation,’ revised in November 2016, mentioned that, ‘Russia will continue to strengthen its comprehensive, equal and trusted partnerships, and strategic collaboration with China and actively develop cooperation with China in all areas. The agreement between the two countries’ fundamental approaches to solving key problems in global politics is considered to be a fundamental part of regional and global stability in Russia. On this basis, Russia will develop mutual cooperation in the areas of foreign policy with China in various ways, including responding to new challenges and threats, solving sensitive regional and global problems, and cooperation in international and multilateral organizations,’ and once again, emphasized that it will cooperate with China in full measure (Russian Federation, 2016).

China's and Russia's concerns over US policies in the Pacific region and Crimean Peninsula had not been fully addressed. In this context, US efforts to deploy its missile defense system in South Korea in 2016 and 2017 further aggravated Chinese and Russian threat perceptions of the USA. They were already concerned that the US had been targeting them with containment policies as part of its rebalancing policy and sanctions against Russia. Moreover, after the THAAD deployment, both China and Russia perceived that they were now confronting an additional threat: a real threat from the US missile defense system.

5.2 Further development of China–Russia ties

The deployment of the US THAAD further strengthened China–Russia defense ties. Most of all, since 2016, the China–Russia strategic and security relationship has become more institutionalized, with the signing of the ‘Comprehensive Strategic Partnership’ in 2016, of the ‘Roadmap on Military Cooperation for 2017–2020’ in 2017, and of the ‘Comprehensive Strategic Partnership of coordination for a new era’ in 2019 (The Diplomat, 2017; Xinhua, 2019a). As they upgraded their security ties with Comprehensive Strategic Partnership initiatives, they agreed to regularize more dialogue platforms at various levels, promote ranks of delegations for several meetings, and expand existing bilateral exercises or launch new ones. Moreover, the ‘Roadmap on Military Cooperation for 2017–2020,’ designed to make top-level design and draw up general plans for China–Russia military cooperation, enabled them to prepare an action plan for joint responses to common threats and for regional peace (The Diplomat, 2017).

A further incremental shift in China–Russia strategic ties was seen in their outstanding military drills after the THAAD deployment was discussed in early 2016. During this period, China and Russia not only extended the existing bilateral drills, but also launched and conducted several brand-new trainings and patrols. First, given the intensifying tension with the USA, China and Russia showed a high level of military engagement through several remarkable exercises. For instance, during discussion over the THAAD deployment between the USA and South Korea, China and Russia held the large-scale Joint Sea 2016 around the South China Sea, deploying various up-to-date military assets. Specifically, the training content and location attracted international attention because this was the first China-Foreign joint naval drill around the disputed South China Sea, showing their resolute will to jointly defend their security and territorial integrity. Moreover, during this exercise, for the first time both countries carried out ‘three-dimensional seizing and controlling of islands and reefs’ involving joint army–navy–air force actions, and also used a joint command information system to proceed with ‘posture sharing, document distribution…[and] command order transmission […] for command posts at all levels and for all combat units’ (Meick, Reference Meick2017: 9). The Joint Sea 2016 demonstrated that both countries had further upgraded the effectiveness of joint drills and constructed a high level of mutual confidence.

China's participation in the existing Russia-led exercises marked another remarkable cornerstone in their incremental defense ties. In 2018, for the first time China officially sent 3,200 troops, 30 aircraft, and 900 tanks to the Vostok-2018 exercise (Carlson, Reference Carlson2018b; Bin, Reference Bin2019). This was the first time China participated in a large-scale Russian exercise on Russian soil. In 2019, following Russia's invitation, China participated in another Russia-led exercise, Tsentr-2019, along with India and Pakistan (CNBC, 2019). These two exercises were conducted in a multilateral format, so that China and Russia not only improved their bilateral defense engagement, but also enhanced interoperability and mutual trust with other countries. One important motive for China's participation in the Russia-led exercise and Russia's acceptance of the Chinese army on its territory was their broad consensus on the growing sense of threat from the USA (Bin, Reference Bin2019: 118).

During the late 2010s, they actively launched new bilateral and multilateral exercises. One noticeable event was the first computer-based joint missile defense exercise Aerospace Security in late 2016. In May 2017, after the USA and South Korea officially announced the deployment of THAAD, Beijing and Moscow held a series of consultations on bilateral cooperation over missile defense, specifically in response to the US missile defense system (Rinna, Reference Rinna2018: 93). In 2017, they conducted the second Aerospace Security in 2017. Given that such a computer-based exercise required both countries to ‘put their cards on the table’ and to disclose their own C4ISR (Command, Control, Communications, Computers, Intelligence, Surveillance and Reconnaissance) systems, the two rounds of Aerospace Security signify that China and Russia had now established a high degree of mutual trust (Blank, Reference Blank2019: 217). That is, confronting a growing threat from the US missile defense system, their joint exercise began to cover missile defense area, which was regarded by both ministers of defense as a breakthrough in the China–Russia military cooperation (Rinna, Reference Rinna2018: 94).

During the late 2010s, China and Russia also initiated new multilateral exercises with other countries. In late 2019, they held the first trilateral naval exercise with Iran around the northern Indian Ocean and Gulf of Oman; in the same year, they conducted another trilateral naval drill with South Africa around the western Indian Ocean (CNN, 2019; Xinhua, 2019b). For both exercises, China and Russia sent advanced military assets and carried out various joint trainings, improving interoperability, coordination capabilities for maritime security, information sharing, and joint mission capacity (Xinhua, 2019b). By consistently expanding their size, complexity, frequency, and geographical reach, China and Russia sent a clear message to the USA that they had become genuine security partners (Rinna, Reference Rinna2018: 93).

Through the third critical juncture period, bilateral cooperation regarding arms transfers and technology has become more vivid and audacious. The dramatic increase in the volume of arms transfers between China and Russia is one concrete indicator of incremental China–Russia ties during this period. Although the downward trend of arms transfers from Russia to China between the mid-2000s and early 2010s stopped in 2012, a practical increase in the volume between 2012 and 2015 was marginal; however, since 2016, the size of bilateral arms transfers has increased exponentially compared to the previous critical juncture periods, and eventually hit a record high for the past decade in 2018 (Figure 2).

Figure 2. Volume of arms transfers from Russia to China (millions of dollars).

Source: Stockholm International Peace Research Institute, SIPRI (2021)

Furthermore, in 2019, it was reported that Moscow would offer to sell China a Su-57E, a variant of the Su-57 which is still under development and will be Russia's fifth-generation multirole stealth fighter (The Diplomat, 2019a). Considering that Russia's ultra-advanced military technology is applied to this next-generation fighter, it is exceptional that Russia attempted to offer it to China in advance of completion. Although China has not yet officially responded to this offer, this event indicates that arms transfers between them have become more decisive than during the past two critical juncture periods.

Moreover, in the late 2010s they initiated joint development in a new area, an early attack missile warning system. At one conference held by the Russian International Affairs Council, Evgeny Buzhinsky, a retired Russian general, implied that there was a high probability of cooperation between China and Russia over a missile attack warning system, and in the same year, President Putin officially announced that Russia was helping China to develop its own such system (The Diplomat, 2019b). Although not a lot of details about their cooperation were revealed, Russia is presumably offering China important technical aid, and resources and data for software development, as well as training for operating personnel (The Diplomat, 2019b). This joint development of a missile attack warning system probably required that the two countries share a huge amount of data on global missiles and rocket launches, and their own missile defense systems, and thus shows that their level of mutual trust once again rose to greater heights.

After the THAAD deployment, the China–Russia strategic cooperation was deeper and wider than before. They increased the size, frequency, and sophistication of joint exercises while also launching new ones; their arms transfer and joint development widened and deepened, and their engagement became more institutionalized. It is noteworthy that, confronting a growing missile threat from the USA, they now focused on enhancement of joint missile defense capabilities. From the Chinese and Russian perspectives, the US THAAD deployment signified a shift in the strategic balance of power in favor of the USA, which imposed threats on the other two countries (Blank, Reference Blank2019: 213). Immediately after the USA and South Korea decided to deploy THAAD, China and Russia issued a joint statement fiercely criticizing their decision, saying they would made significant efforts to enhance their own bilateral strategic coordination (Ruonan and Feng, Reference Ruonan and Feng2017). After that, China and Russia not only launched a computer-based Aerospace Security exercise, but also initiated joint development of a missile attack early warning system.