With the expiration of New START, a familiar refrain has returned to the arms control debate: that this is the first time in 50 years that the major nuclear powers have been without a strategic nuclear arms control agreement. It is a powerful talking point. It is also historically inaccurate — and that matters, because misreading the past leads to poor policy prescriptions for the future.
The reality is that nuclear arms control has never been continuous or linear, and it certainly hasn’t been independent of geopolitics. Even the first major strategic arms control agreement, the 1972 SALT I Interim Agreement, underscored the contingent nature of Cold War arms control. Explicitly temporary (five years) and limited in scope, it reflected the balance of power and political circumstances of the moment rather than a durable or comprehensive framework for strategic restraint.
Long stretches of the Cold War passed without ratified strategic arms treaties in force. SALT II, signed in 1979, was never ratified and never entered into legal force. Although both sides largely observed its limits until 1986, there was no binding, verifiable treaty governing strategic nuclear forces until START I entered into force in 1994. That gap alone — stretching from the late 1970s into the early 1990s –undermines claims of an unbroken half-century of formal strategic arms control.
Nor was that period an aberration. Arms control during the Cold War was episodic and constrained, shaped by rivalry rather than cooperation. Agreements like the Anti-Ballistic Missile Systems Treaty (the ABM Treaty, part of the SALT talks and also signed in 1972) and, later, the Intermediate Nuclear Forces (INF) Treaty , signed in 1987, addressed specific categories of systems or stability concerns. They were important, but they did not represent a steady march toward disarmament. They were narrow bargains struck under particular political conditions.
A Transformed Political Environment
What fundamentally changed in the late 1980s was not negotiating technique. It was geopolitics.
The most ambitious advances in arms control — the elimination of entire classes of weapons under INF and the deep, verified reductions mandated by START I, which entered into force in December 1994 — came only as the Cold War was ending. These agreements were products of a transformed political environment: the easing of ideological confrontation and internal change within the Soviet Union and its satellite nations. Arms control succeeded at scale because the strategic environment made it possible, not because arms control itself altered the underlying rivalry.
That historical reality is often lost in today’s debate, particularly in discussions surrounding New START, which entered into force in February 2011.
I supported New START when it was negotiated, and I supported the five-year extension agreed to in 2021. At the time, extending the treaty preserved a measure of transparency and predictability in the U.S.–Russia strategic relationship and avoided an abrupt collapse of the last remaining bilateral arms-control framework.
But New START was very much a product of its time. It was designed to regulate bilateral nuclear relations between the United States and Russia in a relatively benign geopolitical environment, one that was shaped by post-Cold War assumptions regarding strategic stability, limited great-power rivalry, a narrow focus on deployed strategic forces, and to facilitate further nuclear reductions between the United States and Russia. It was not designed to manage the strategic environment we face today.
Those limitations became apparent well before the treaty’s formal expiration. On-site inspections under New START stopped in 2020 due to the COVID pandemic and never meaningfully resumed. In 2023, Russia halted data exchanges that had been required under the treaty, in response to U.S. support for Ukraine against Russia’s full-scale war, further hollowing out the treaty’s transparency and verification functions. And legally, the treaty allowed only a single five-year extension; there was no mechanism to extend it further.
The China Factor
In short, New START helped manage risk in a specific historical and geopolitical context. It was not built to regulate a deteriorating strategic relationship marked by open conflict, deep mistrust, rapid technological change, and more significantly, the emergence of additional nuclear peers.
That last point is decisive. The central strategic challenge confronting the United States today is the rise of China and its rapid, unconstrained nuclear buildup. Beijing is expanding and diversifying its nuclear forces at a pace that directly affects U.S. force structure, extended deterrence commitments, and escalation management in the Indo-Pacific.
For example, as the U.S. Department of Defense noted last year in its annual China military power report: “China’s stockpile of nuclear warheads remained in the low 600s through 2024, reflecting a slower rate of production when compared to previous years. Despite this slowdown, the PLA has continued its massive nuclear expansion…[and] the PLA remains on track to have over 1,000 warheads by 2030.”
Unlike the U.S.–Soviet competition of the Cold War, the United States now faces the prospect of deterring two near-peer nuclear adversaries simultaneously, a challenge for which existing bilateral arms control frameworks were never designed.
In many ways, this strategic reality also contributed to the demise of the INF Treaty. While INF constrained U.S. and Russian ground-launched intermediate- and medium-range missiles, it imposed no limits on China, which over the past 20 years has deployed large numbers of precisely those systems as a central pillar of its regional military strategy. It’s a reminder that arms-control agreements that fail to account for the most consequential drivers of military competition are unlikely to endure.
This raises the fundamental question of how China can eventually be brought into a future arms control framework — a challenge I have addressed elsewhere. Indeed, every U.S. administration since the Clinton administration has sought, unsuccessfully, to engage China on this issue. To date, Beijing has consistently refused to participate in meaningful diplomatic discussions or negotiations on nuclear arms control. While this posture may have been tolerable when China possessed only a few hundred nuclear warheads, it is no longer sustainable given China’s current and accelerating nuclear buildup. History suggests that China may be most willing to come to the negotiating table only when faced with deployments by others that impose tangible strategic and economic costs — much as NATO did in response to Soviet INF deployments. Regrettably, this implies that the United States may first need to expand certain military capabilities to create the conditions necessary for eventual arms control.
Arms Control for the Future
Looking ahead, this does not mean arms control is obsolete. It does mean, as I wrote last year in Just Security, that it must be reimagined. Any future framework capable of contributing to strategic stability will need to move beyond Cold War-era bilateralism and focus instead on a combination of risk reduction, transparency measures, crisis communication mechanisms, and selective constraints that reflect a multipolar nuclear environment. Such an approach may be more modest than past treaties, but it would be better aligned with today’s realities — and more sustainable over time.
This is why declaring that today’s moment is unprecedented misses the point. What is genuinely new is not the absence of a treaty, but the absence of a strategic environment conducive to the kind of arms control that flourished briefly at the end of the Cold War. Treaties do not exist in a vacuum. They follow geopolitics; they do not override it.
The world without New START is dangerous, but not because it represents a break from a mythical 50 years of uninterrupted restraint. It is dangerous because it reflects the return of hard-edged geopolitical competition. Recognizing that reality is the first step toward building arms-control approaches that can actually work in today’s geopolitical and strategic environment.
