Mapping Global Strategic Stability in the Twenty-First Century
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Dmitry V. Trenin

National Research University–Higher School of Economics, Moscow, Russia
Faculty of World Economy and International Affairs
Research Professor;
The Primakov Institute of World Economy and International Relations (IMEMO),
Moscow, Russia
The Center for International Security
The Sector for Non-Proliferation and Arms Limitation
Lead Researcher

The U.S.-Russia strategic relationship—the only one to have featured strategic arms control—is no longer central to global strategic stability. While Sino-American relations are not nearly as dominant in terms of the rest of the world as U.S.-Soviet relations were during the Cold War. Thus twentieth-century methods of dealing with the issue of strategic stability, such as arms control, are insufficient.

As the world experiences a palpable weakening of the global order—complete with major-power rivalry, regional instabilities, and technological innovation—strategic stability, taken for granted since the end of the Cold War, is again in question.

Yet the renewed discussion of strategic stability is too often focused on relations between the United States and Russia, and leads to calls for updated arms control. Seeking twentieth-century solutions for twenty-first-century problems, however, is hardly productive. This article discusses how the meaning and key features of strategic stability have changed since the bipolar era, the toolbox that exists today for managing strategic stability, and which policies should be adopted by the powers concerned.


The notion of strategic stability first emerged in the middle of the Cold War, after the 1962 Cuban missile crisis had brought the United States and the Soviet Union to the brink of an all-out nuclear exchange. Back then, strategic stability essentially meant an absence of stimuli for either of the two rival superpowers to deliver a first nuclear strike. Stability required each of the two powers to have a credible second-strike capability that would render the first strike pointless. Mutually assured destruction meant that the country that fired its nuclear weapons first was guaranteed to be destroyed second, minutes after its enemy had been hit. To ensure that destruction really would be mutual, both the United States and the Soviet Union agreed to put severe limits on their strategic defenses by concluding the Anti-Ballistic Missile Treaty in 1972. 

In this way, both Cold War adversaries were sufficiently deterred from seriously considering attacking each other. Stability was upheld by rough parity in strategic nuclear arsenals, which the Soviet Union had achieved by the late 1960s. Conventional military resources were less symmetrical for geographical and geopolitical reasons, but the prevailing understanding on both sides was that a “central war” between the Warsaw Pact and NATO would not stay conventional for more than a few hours, and that a nuclear war, once started, would likely escalate to the strategic level and become global. The Soviet military doctrine pointedly dismissed U.S. strategists’ notion of a limited nuclear war in Europe that would leave the United States unscathed.

Since both sides agreed that an all-out nuclear war would probably destroy the world and therefore could not be “won” in any meaningful sense, this also drastically reduced the possibility of a direct conventional war between NATO and the Warsaw Pact. The standoff in Europe, where most of the rival blocs’ forces were concentrated, was therefore static and, in principle, stable. Throughout the entire duration of the Cold War, real (“hot”) wars were fought outside the central theater of confrontation, usually by proxies, as in the Middle East or Southern Africa, or with only one of the two superpowers directly involved, as in Korea, Vietnam, or Afghanistan. After 1962, there were no more crises in Berlin.

The Cold War was hardly a paragon of stability and mutual trust, of course; quite the opposite. Fear of a first strike by the adversary was pervasive. Even after the Cuban missile crisis, there were several occasions when one side mistakenly believed it was under missile attack from the other. Even in calmer periods there were constant concerns of global or regional balances being eroded or overturned, creating strategic advantages for the opposite side.

The ever-spiraling arms race was eminently destabilizing, even as it held out promises and created fears of one party gaining an advantage big enough to break out of the mutual suicide pact. Deployments of medium-range nuclear-armed missiles, as in Europe in 1983, created risks of “decapitating” first strikes, as did the 1983 Able Archer exercise and the prospect of deploying weapons in space, e.g., under U.S. President Ronald Reagan’s Strategic Defense Initiative (SDI) program. On the other hand, U.S.-Soviet arms control negotiations, started in the late 1960s, and the agreements they produced created a degree of reassurance.

The key features of Cold War–era strategic stability included:

— a bipolar global system with just two major adversaries;
— mutual expectations that any war between the two superpowers would go nuclear, and rise to the strategic level;
— a degree of confidence that the prospect of mutually assured destruction would deter both sides from attacking each other;
— a constant fear that the adversary would find a way to break out of the mutual suicide pact;
— bilateral arms control as a method of limiting the arms race, and arms control negotiations as a way for the two antagonists to adjust to the strategic status quo.

The four decades of the Cold War did remain cold, and there is little doubt that nuclear deterrence played a major role in that. Yet deterrence was no guarantee of stability: it could easily have failed, and on several occasions, including the Cuban missile crisis, humanity was simply lucky. The twenty-first century has a very different strategic landscape, and an entirely different set of challenges that necessitate entirely new ways of ensuring strategic stability. 


The end of the Cold War ushered in a quarter-century of U.S. global dominance, unprecedented for any nation in world history. Relations between the United States and the few great powers, Russia among them, were amicable. Pax Americana, in the sense of peace among all the major powers, became a reality. However, this dominance did not eventually lead to a stable global system accommodating all the important players. By the middle of the 2010s, the amicable interlude was over, and great-power rivalry was back. Strategic stability again became an issue.

The global strategic landscape, however, has changed substantially. Instead of the Cold War’s rigid bipolarity, and the Pax Americana’s unipolarity, there are several independent players in the game. The United States, though no longer as dominant as it was right after the end of the Cold War, remains the strongest power by far. It also remains the leader of NATO, to which two other nuclear powers, the United Kingdom and France, belong. America faces a comprehensive challenge from China, however, and is in a confrontation with Russia. By contrast, China and Russia, officially designated by the United States as rivals and adversaries, describe each other as strategic partners. India, an emerging global power, is friends with Russia and America, but fears China. There are therefore four major nuclear-armed players, relations among which are complicated. 

At the regional level, there are a number of powers that have developed and deployed nuclear weapons: Israel, Pakistan, and North Korea. While the Israeli nuclear arsenal is widely considered to be a weapon of last resort, Pakistan’s nuclear systems are trained on India, and North Korea has worked to achieve crude deterrence of the United States. Each of the three countries is vociferously independent, despite Israel’s long-standing links with the United States, Pakistan’s close but uneasy relations with Washington and its quasi-alliance with Beijing; and North Korea’s formal ties to China. Essentially, all three countries are independent nuclear-armed players.

Nearly two decades into the twenty-first century, nuclear proliferation has not produced dozens of nuclear weapons states, as was feared when the Non-Proliferation Treaty was signed in 1968, but it has allowed a substantial expansion of the nuclear club: India, Pakistan, and North Korea are important additions. Nuclear multipolarity has become a fact, and the process is not yet over. Essentially, virtually any country with some resources and a strong and single-minded leadership can achieve nuclear status if it is prepared to bear the cost of ostracism and possibly military strikes against it.

The U.S. war in Iraq, the NATO operation in Libya, and, some would add, Russia’s intervention in Ukraine have shown that nuclear disarmament renders regimes vulnerable to outside intervention. On the other hand, as North Korea has demonstrated, nuclear weapons capable of reaching the United States or hitting its close allies may be the only credible guarantee of immunity for the regime that has deployed them. Iran, a regional power in the Middle East, has agreed to rein in its nuclear program in exchange for reintegration into the global economy, but should the 2015 agreement, known as the JCPOA, fall through, there is nothing—including potential U.S. or Israeli strikes—that would prevent it from acquiring nuclear weapons.

States are not the only potential users of nuclear weapons. Since 9/11, the possibility of non-state actors gaining access to nuclear weapons has been a constant cause for concern among national security officials. In terms of strategic stability, there are fears of a false-flag attack, in which a terrorist group intentionally provokes a conflict between major powers. In the atmosphere of a near-total lack of trust, e.g., between the United States and Russia, proving the truth will be more challenging than ever before.

On the technology side, the advent of strategic non-nuclear weapons, progress in cyber technology, the dawn of artificial intelligence, and the potential emergence of space-based weapons are all impacting on strategic stability. A combination of systems based on these types of technology and nuclear weapons could destabilize the strategic environment. Highly accurate non-nuclear systems with a global reach allow advanced military powers to carry out strategic attacks with conventional munitions, and nuclear and non-nuclear systems are also closely entangled with each other.

Cyberattacks in particular can impair the enemy’s deterrence capacity before a nuclear strike. Cyber weapons can also attain objectives that formerly could only be achieved through the use of nuclear weapons, such as switching off power grids in major cities or paralyzing infrastructure in whole countries. The difficulty in attributing the source of such attacks and uncertainties about retaliation for them makes strategic stability even harder to achieve.

In summary, the new features impacting on strategic stability in the twenty-first century include:

— nuclear multipolarity and, following on from that, the fragmentation of global strategic stability;
— the revival of strategic rivalry among the world’s four major military powers;
— the enhanced role of regional powers and even third-tier players, such as North Korea;
— potential for nuclear terrorism and false-flag attacks;
— the advent of strategic non-nuclear systems capable of performing tasks formerly assigned to nuclear weapons;
— the close entanglement of nuclear and non-nuclear systems, making it difficult or impossible to distinguish between the two;
— the emergence of advanced powerful technologies, such as cyber, that can be used in combination with nuclear weapons, or independently from them.


It should be clear from this analysis that twentieth-century methods of dealing with the issue of strategic stability, such as arms control, are insufficient. In addition, U.S.-Russian arms control is in trouble as a result of the serious deterioration in relations between Moscow and Washington. In 2002, the United States withdrew from the 1972 Anti-Ballistic Missile (ABM) Treaty—which the Russians had always regarded as a cornerstone of strategic stability—and it has engaged in a missile defense program designed to protect U.S. territory and its key allies. Even though this program is unlikely to erode Russia’s deterrence capability in the foreseeable future, its long-term potential remains a concern to Moscow’s strategic planners.

Another U.S.-Soviet treaty of supposedly unlimited duration, the 1987 Intermediate-Range Nuclear Forces (INF) Treaty, looks set to be scrapped after U.S. President Donald Trump said his country plans to withdraw from the treaty amid mutual allegations of its violation. This means the specter is looming once again of a nuclear missile force belonging to a notional adversary positioned in close proximity to one’s political and command headquarters. It would reduce reaction time to just a few minutes and dangerously undermine strategic stability.

The other treaty aimed at reducing U.S. and Russian strategic nuclear weapons, New START, is due to expire in 2021, unless it is extended for another five years. Even if the New START can be salvaged, traditional nuclear arms control is unlikely to play the central stabilizing role that it did in the twentieth century.

Firstly, the U.S.-Russia strategic relationship—the only one to have featured strategic arms control—is no longer central to global strategic stability, despite the fact that Washington and Moscow still control about 90 percent of the world’s nuclear weapons. For political reasons, no new arms agreement with Russia, even if negotiated by the U.S. government, has a chance of being ratified by the U.S. Senate in the foreseeable future.

In contrast, the U.S.-China relationship, which is more consequential for the future of the world order, has never had an element of arms control to it. Beijing has rejected the notion of subjecting its relatively modest nuclear arsenal to treaty limitations negotiated with Washington, and this position is unlikely to change. Moreover, Sino-American relations are not nearly as dominant in terms of the rest of the world as U.S.-Soviet relations were during the Cold War.

Secondly, the strategic environment has become very fragmented due to the rise of regional and local players with sizeable nuclear arsenals. These countries are not controlled by Washington or Beijing and would act on their own.

Thirdly, the arrival of technologies that are about capacity rather than numbers makes traditional means of control by imposing numerical limitations difficult or impossible.

Finally, cyberattacks that can paralyze a country’s vital systems are notoriously difficult to attribute with any certainty.

Not all of the Cold War legacy is inoperable, however. Unlike arms control agreements, various trust-building measures and conflict-prevention mechanisms have a better chance of being adopted for the needs of the twenty-first century.


In this new environment of prevailing unilateralism and technological challenges, a premium should be put on providing various guardrails to the increasingly adversarial relationship between the United States and China, and the openly confrontational one between the United States and Russia. In the latter case, reliable real-time 24/7 communication between top military commanders, security chiefs, and political leaders, and agreed protocols for de-conflicting and escalation prevention make the most sense to avoid misinterpretation and make sure that dangerous incidents do not escalate and lead to serious clashes.

Unlike during the Cold War, incidents rather than premeditated surprise attacks are the main hazard of the current era. In fact, this method of conflict avoidance is already functioning between the United States and Russia in Syria. More of this should follow, including between Russia and NATO.

To avoid strategic misperception, the leaders and senior officials of all major military powers need to keep in touch with each other and have a clear understanding of the respective country’s policy objectives, strategies, and tactics. This is difficult, particularly between Moscow and Washington, because of the breakdown in mutual trust, but it is crucial. Trust may not be a realistic objective, but a degree of mutual confidence can and should be. Communication between military chiefs should be supplemented by regular dialogue involving heads of national security councils and intelligence directors.

Such dialogue could be organized around discussions on extending the New START treaty, but does not have to be limited by them. Americans and Russians may have found forging a partnership awkward, but they have proven that they are capable of managing their own adversity. A multilevel dialogue on strategic stability would itself be stabilizing. In the course of the dialogue, Russians need to find a way to better articulate the rationale for the policies and strategies that they adopt, to reduce misunderstanding and misperception on the Western side, which may be dangerous in a crisis. There is also still room for Russians and Americans to discuss regional nuclear stability issues, in particular, with reference to North Korea and Iran.

This material is a part of “XXI Century Strategic Stability” project, supported by the UK Foreign and Commonwealth Office.