U.S.-China nuclear and strategic stability will be tested in the coming year after a spate of revelations in 2021 about Beijing’s nuclear program. It is expanding the size and sophistication of its arsenal, potentially growing its total stockpile to 1,000 warheads by 2030, or just over a quarter of America’s 3,800 warheads. China also has tested a weapon system that flies into orbit carrying a hypersonic weapon — missile systems that fly five times the speed of sound and can maneuver to avoid defenses — and dug hundreds of new silos for intercontinental ballistic missiles (ICBMs). In addition, Beijing is reportedly consolidating its nuclear triad of bombers, submarines, and ICBMs; moving to a launch-on-warning posture; and exploring new “exotic” nuclear systems.

These developments raise questions about what is motivating China to pursue such capabilities, how nuclear modernization connects to the larger regional security dynamic, and how Washington should respond. The multitude of technical intricacies in this area — from the features of particular weapons systems to nuclear deterrence logic — are (understandably) often difficult for non-specialists to get their arms around. It is possible to understand the overall picture, though, by examining the issues as four concentric circles that show how nuclear-specific issues intertwine with broader concerns in both Beijing and Washington about advanced conventional capabilities and U.S.-China competition overall.

Nuclear Weapons and Missile Defense 

The first and innermost circle contains the nuclear weapons themselves, along with missile defenses, including the advancements mentioned earlier. China’s objectives are not all clear. Beijing certainly wants to ensure it can conduct a retaliatory strike if the United States or another country bombed China first; that capability undergirds nuclear deterrence. Chinese leaders likely also seek to deter the United States from credibly threatening to use nuclear weapons in a regional conflict, say over Taiwan, if China gained an advantage with its conventional forces.

Another more speculative ambition, but one voiced by the head of U.S. Strategic Command, among others, is that China is trying to “break out” of being a second-tier nuclear power and sprint to parity with the United States and Russia. This would constitute a sea change in Beijing’s nuclear strategy, but it would be consistent with President Xi Jinping’s stated aim to build a “world-class military” generally and “high-caliber strategic deterrence systems” specifically. China under Xi has carried out a more aggressive foreign and security policy across the board. Plus, military power and prestige help boost the regime’s legitimacy at home as well as its global status.

Of course, the situation is interactive, and some U.S. nuclear policies have likely exacerbated the security dilemma and motivated Beijing to respond. These include the Trump administration withdrawing from several arms control agreements, developing new nuclear weapons with lower yields designed to be more useable, and continuing to improve strategic missile defenses. (The Biden administration is set to articulate its positions on these issues in its Nuclear Posture Review due early next year.)

Advanced Conventional Weapons and Emerging Technologies 

The second circle that illustrates how nuclear-weapons issues intersect with broader concerns includes non-nuclear systems that are capable of strategic effects, a nebulous term that generally means massive destruction that shapes the character of a conflict. Indeed, some experts argue that the current nuclear age will be defined as much by non-nuclear capabilities, such as advanced conventional weapons and emerging technologies.

Among these are conventionally armed ballistic, cruise, and hypersonic missiles of various ranges. China has the world’s largest arsenal of such missiles that can be fired from land, a fact that played a big role in the U.S. decision to withdraw from the Intermediate-Range Nuclear Forces (INF) Treaty in 2019. Like those of other nations, some Chinese missiles and aircraft are designed to carry either conventional or nuclear warheads, making it difficult for adversaries to distinguish what they might face during a conflict. Further, some missile units operate conventional forces in the same bases as nuclear ones. Specialists call the problem this creates entanglement because U.S. strikes targeting conventional forces could hit nuclear ones unintentionally.

China likewise worries about U.S. conventional missiles that might be powerful enough to destroy a large portion of Beijing’s previously bare-bones nuclear arsenal, leaving U.S. missile defenses to intercept the remainder and thereby prevent China from retaliating. The two countries also rely on satellites and radars for early-warning and command-and-control functions for both nuclear and conventional systems. Those could be blinded, disabled, or destroyed with various types of anti-satellite weapons or cyberattacks.

Several emerging technologies also look likely to have a disruptive effect on the nuclear and strategic balance, even if the full extent of their impact is not yet known. These include unmanned and autonomous systems — colloquially, drones — that could make policymakers less worried about human pilots being killed and therefore more willing to take risks in employing those weapons during a crisis or conflict. In addition, artificial intelligence and quantum computing applications present the twin possibilities of reducing the time governments have to make decisions in a crisis and creating destabilizing transparency by undermining stealth and making encrypted communications decipherable.

Regional Flashpoints 

The third circle shows that the aforementioned military capabilities are arrayed in an East Asian region featuring several major flashpoints. These include obvious U.S.-China hotspots such as Taiwan and territorial disputes in the East and South China Seas. It also includes indirect flashpoints such as the Korean Peninsula and the Sino-Indian border. Tensions are rising over nearly all of them. These hotspots both motivate China’s military buildup and could be the reason tensions boil over.

Moreover, China engages in persistent gray zone warfare — actions inhabiting the space between peace and war — in these areas. Beijing’s activities often implicate U.S. security commitments to allies and close partners, including Japan, South Korea, the Philippines, and Taiwan. Gray zone warfare is designed to stay below the threshold of conflict but inherently raises the risk of uncontrolled escalation. During a war, China plans to target U.S. and allied bases with missiles. U.S. allies are considering developing their own missiles that could strike mainland China in response. In short, the existence of multiple regional flashpoints provides ample opportunities for a crisis to ignite the volatile mix of military forces described above.

U.S.-China Rivalry 

The fourth and outermost circle showing the overlap between nuclear concerns and broader issues contains the overall U.S.-China relationship. Washington and Beijing are feuding across nearly every dimension of bilateral relations — not just the military sphere but also in economics, diplomacy, technology, and governance. The superpowers lack a common framework to guide their bilateral relations following the end of the “engagement” era that began when President Richard Nixon went to China nearly 50 years ago. And Chinese leaders see U.S. criticism of human rights abuses, along with efforts to constrain China’s advancement as a technological and military power, as designed to undermine support for the Chinese Communist Party government and, at the extreme end, pursue regime change.

Questions about the trajectory of global power underlie the rivalry between Washington and Beijing. Chinese leaders see their country as a rising power and the United States as declining, a transition Xi alludes to by saying the world is going through “changes unseen in a century.” The accuracy of that assessment is questionable, to say the least, but it nevertheless appears to be the predominant view in China. Beijing believes Washington is therefore working to thwart China’s rise. For their part, U.S. officials view China as trying to undermine American alliances in the region and overturn the rules-based order that dates back to the end of World War II.

Seeking Stability 

Taken together, the U.S.-China nuclear and strategic relationship appears increasingly unstable across all four of these areas, which intertwine to create a feedback loop of instability. How, then, to make progress? Joe Biden and Xi Jinping agreed to “carry forward” talks on strategic stability following their virtual meeting in November. Those talks and associated efforts should follow four principles.

First, expect slow progress, if any, and remember there are no silver bullets. Any serious process will take significant time to bear fruit, and U.S.-China discussions on these topics have made scant headway despite years of attempts. Those outcomes are unlikely to change quickly.

Second, address discrete issues but keep in mind how they fit into the larger picture. A future U.S.-China arms control and strategic stability regime, if it happens, will almost surely be made up of a patchwork of agreements on specific topics, for example, an agreement on notification of ballistic missile launches. Talks should identify concrete opportunities for progress but must ensure those actions continue to align with the larger geopolitical picture as well. This includes assessing where nuclear capabilities serve to offset imbalances in the conventional military power.

Third, involve other countries when it can be beneficial. U.S.-Russia-China trilateral talks are both unlikely and probably would not be productive, given the Sino-Russian entente’s enmity toward the United States and Moscow’s reluctance to be seen as pressuring Beijing in any way. But a format involving the Permanent Five members of the United Nations Security Council (P5, comprising the United States, China, Russia, France, and the United Kingdom) could provide a useful forum with less of the intense political scrutiny that bilateral U.S.-China talks receive. In addition, consultations on strategic issues with U.S. Indo-Pacific allies — especially Japan, South Korea, and Australia — should proceed in parallel to ensure close coordination on extended deterrence and on addressing the impact of new capabilities on the regional security environment.

Fourth, keep threat assessments grounded in military-technical and operational realities. As noted above, China is modernizing its nuclear and strategic arsenal in major, even alarming, ways. But some assessments appear to be calling attention to these shifts by being “clearer than truth” and overstating the implications. That is the wrong approach. U.S. policymakers should remain clear-eyed about changes to China’s nuclear posture while avoiding alarmism. They should also bear in mind when and how U.S. actions might contribute to arms racing incentives.

The U.S.-China nuclear and strategic relationship has entered a new stage. Navigating it successfully to uphold deterrence and sustain regional peace and security will require a comprehensive approach that takes into account all four concentric circles and formulates sober, purposeful responses. Pursuing nuclear and strategic stability between the United States and China will likely prove harder than ever — but it is perhaps more important than ever, too.

IMAGE: U.S. President Joe Biden meets with China’s President Xi Jinping during a virtual summit from the Roosevelt Room of the White House in Washington, DC, Nov. 15, 2021. (Photo by MANDEL NGAN/AFP via Getty Images)