In recent years, China and Russia have strengthened their bilateral ties. But what characterizes the Sino-Russian alignment and its effects? Under what circumstances are the two nations inclined to provide military support to each other, and in what manner? A new paper by FSI Center Fellow Oriana Skylar Mastro delves into these questions, shedding light on how military cooperation between Beijing and Moscow could potentially reshape the global security landscape.

Published in the journal Security Studies, the paper, Sino-Russian Military Alignment and Its Implications for Global Security, underscores the multifaceted nature of the Sino-Russian military alignment, emphasizing mutual support, economic benefits, and potential collaboration in conflicts involving other nations. "Understanding the depth and breadth of the military alignment between China and Russia is crucial for assessing their combined capabilities and potential impact on global security dynamics," Mastro writes.

Mastro, a political scientist and expert on Chinese military and Indo-Pacific security, introduces a novel framework for assessing military alignment between great powers, capturing different degrees of alignment from low to moderate to high. Using metrics relevant to warfighting, she considers four categories of activity: provision of weapons and equipment, defense industrial base collaboration, coordinating mechanisms, and operational preparations. By evaluating the depth of alignment based on activities in each category, Mastro gauges countries' ability to support each other during wartime, focusing on the Sino-Russian military relationship as a case study.

Her findings indicate that most Sino-Russian activities have become more frequent, expansive, and deeper. Moreover, the alignment is focused on facilitating China’s challenge to U.S. hegemony in Asia, even though recent activities suggest a movement toward directly supporting China in wartime.

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A New Framework for Understanding the Sino-Russian Relationship

Mastro’s research is based on information gathered from open-source reporting on China and Russia’s relevant military activities, specifically government documents, reports, and media coverage in English, Chinese, and Russian from 2005 through 2022. Her analysis encompasses two types of alignment behavior: (1) how countries help build each other’s independent ability to fight and (2) how they might strengthen the ability to fight together. It also considers three alignment indicators in the Sino-Russian case: (1) whether the two countries engaged in alignment activity in the past twelve years; (2) whether the activity occurred occasionally or routinely; and (3) whether both countries engaged equally.

The research unveils the increasing frequency and depth of interactions between China and Russia, particularly related to joint military exercises. Mastro’s framework shows that “moderate” or “high” alignment activities — such as joint development, invitations to military exercises at home, and cooperation agreements on logistics — have all occurred only within the past five years. The two countries have conducted six joint military operations in or over the East China Sea since 2019. The sixth joint operation, an air patrol, took place in June 2023, amidst tensions over Taiwan and the war in Ukraine.

In addition to increased joint operations, the two countries actively bolster each other's military capabilities: from joint development projects to logistic support agreements, agreements for satellite cooperation, and ground-monitoring stations, the Sino-Russian military activities alignment is deepening. Still, the coordination and readiness of the two countries for joint operations are focused mainly on support roles such as intelligence and space access rather than direct combat preparations.

Mastro finds that the Sino-Russian alignment is geared towards enhancing China's ability to counter the United States in Asia, rather than preparing for joint operations against the United States and its allies. “Additionally, there are almost no indications that the two countries would consider joining military capabilities to achieve goals outside their regions,” she writes. In terms of direct combat support, her findings show that both China and Russia have not explicitly voiced support for each other's territorial ambitions. Instead, both parties appear to establish favorable circumstances for Russia to boost China's independent military capacities during peaceful times and provide a strategic support base during conflicts. By offering support functions, Russia can aid China in achieving success while retaining a degree of plausible deniability.

Mastro’s framework also reveals the asymmetric nature of the Sino-Russian relationship, with Russia seemingly more willing to support China's objectives than vice versa. She notes that “China’s lackluster response to Russia’s invasion of Ukraine is consistent with this finding.” Russian policymakers seem to recognize the net value and opportunity provided by their “pivot to the east,” even if it is asymmetric. While China gains more by becoming the regional hegemon in Asia, “the outcome puts Russia in a better position overall strategically, but also economically and politically.” Essentially, Moscow stands to gain more relative power against the United States through its partnership with Beijing than it sacrifices by empowering China. The bilateral alignment serves Russia's broader strategic aim of undermining U.S. dominance, thus advancing its security interests and regional goals.

Implications for U.S. Defense Planning

Mastro deduces that China and Russia are not preparing to fight a high-intensity conflict against the United States together, but may provide indirect support — equipment, war materiel, and intelligence. She cautions that “in the case of great power alignment, even such indirect support can have a significant impact on the balance of power.”

First, the Sino-Russian alignment allows both countries to focus on countering the United States and its allies, with reduced military forces needed on the Russia-China border due to non-aggression pacts and confidence-building measures.

Second, even without direct support for Chinese military operations, Russia's role in training and equipping China's military poses challenges for the United States. This assistance strenghtens Beijing's capacity to counter U.S. strengths in air and maritime warfare. Opportunities also remain for Russia to enhance China's capabilities, particularly in areas like air defenses and submarine technologies. Past joint exercises have provided valuable training for China, particularly in maneuver and network-centric warfare.

Furthermore, mutual support between China and Russia could weaken U.S. deterrence efforts in peacetime and wartime. China's continued purchase of Russian oil and gas has helped Russia offset some of the losses from Western sanctions in response to its invasion of Ukraine, bolstering its ability to sustain the war. As the two countries have created mutually supporting defense industrial bases, Russia is becoming even better suited to serve as a strategic rear, an extension of China’s production capability. Russia also has the potential to diminish China's dependence on maritime routes, which are susceptible to U.S. attacks, for oil access by ramping up its provision of oil and gas through overland routes to China.

While the Sino-Russian alignment is limited to facilitating China’s challenge to U.S. hegemony in Asia, still, if China goes to war over Taiwan, Russia is likely to offer support in the form of equipment, intelligence, and critical war supplies. Russia may also establish restricted zones near the conflict area under the pretext of homeland defense, hindering U.S. efforts to achieve air and naval dominance. These actions, categorized as "alliance gray zone" activities, allow each country to exploit the relationship to its operational advantage without direct combat involvement. Such tactics would make it challenging for the United States and its allies to compel China and manage escalation.

Finally, the history of Sino-Russian joint air patrols suggests that the greatest area of cooperation between them will be in a conflict involving Japan. In such a scenario, Russia could establish defensive air patrols in Northeast Asia, ostensibly for homeland defense purposes, effectively denying U.S. access to the region. This strategy would create safe zones for Chinese offensive operations, deplete Japanese resources, and challenge U.S. air and naval superiority. As Japan reinforces its defense capabilities and aligns more closely with the U.S. on regional issues like Taiwan, China may counter by increasingly turning to military collaboration with Russia.

These potential impacts on the balance of power in Asia underscore the need for the United States to monitor and adapt to the evolving dynamics of the Sino-Russian military alignment.​​