What are the potential long‑term effects of the U.S. and Russia’s decision to maintain observation of the New START framework post‑expiration on global arms control architecture and emerging nuclear powers’ treaty strategies?
The expiration of the New START treaty on February 5, 2026 marks the first time since 1972 that no legally binding limits govern the strategic nuclear arsenals of the United States and RussiaIs it time to START worrying? Nuclear restraint is about to fade without a fightrt +1. While Russian President Vladimir Putin proposed in September 2025 that both sides voluntarily observe the treaty's central limits for one year, and media reports suggest negotiations toward informal adherence may be underway, no formal mutual commitment has been confirmedFears grow of new nuclear arms race as key U.S.-Russia treaty expiresnbcnews +1. The potential consequences of any informal observation framework—or its absence—carry profound implications for global arms control architecture and the strategic calculations of emerging nuclear powers.
The scenario of informal adherence to New START's central limits—1,550 deployed strategic warheads and 700 delivery systems per side—draws direct precedent from the SALT II experience of 1980–1986Strategic Arms Limitation Talks II (SALT II) - Arms Control Associationarmscontrol . After President Carter withdrew SALT II from Senate consideration following the Soviet invasion of Afghanistan, both superpowers pledged to observe its terms informallyStrategic Arms Limitation Talks - Wikipediawikipedia . However, this arrangement ultimately collapsed when President Reagan determined in May 1986 that Soviet violations made continued observance untenable, declaring that future strategic decisions would be based on "the threat posed by Soviet forces and not on standards contained in the SALT structure"Statement on Soviet and United States Compliance With Arms Control Agreements | Ronald Reaganreaganlibrary +1.
The SALT II precedent reveals both the potential and the limitations of informal frameworks. While such arrangements can provide temporary stability, they remain vulnerable to erosion through:
The loss of New START's verification regime represents perhaps the most significant immediate consequence of the treaty's expiration. The treaty's provisions included 18 annual on-site inspections, regular data exchanges on numbers and locations of treaty-accountable systems, unique identifiers for each ICBM, SLBM, and heavy bomber, and telemetric information sharing during missile flight testsVerification - State.govstate .
Without these mechanisms, both sides must rely exclusively on National Technical Means (NTM)—primarily satellite reconnaissance—to monitor compliance[PDF] National Technical Means (NTM)aerospace . While commercial and military satellite capabilities have advanced significantly since the Cold War, experts propose that a framework relying on "Cooperative Technical Means" could preserve transparency through:
However, such measures would require active cooperation that may be politically difficult to achieve in the current environment. Vasily Kashin of Moscow's Higher School of Economics has warned that without limitations and negotiations, "both countries will plan for the worst case scenario," increasing the risk of miscalculationFor the first time in decades, the U.S. and Russia have no limits on nuclear weaponsmichiganpublic .
The timing of New START's expiration carries particular significance for the broader nonproliferation regime. The 2026 Review Conference of the Nuclear Non-Proliferation Treaty convenes in April—just two months after the treaty's lapseThe US and Russia’s nuclear weapons treaty is set to expire. Here’s what’s at stake | Chatham House – International Affairs Think Tankchathamhouse +1. Under Article VI of the NPT, nuclear-weapon states are obligated to pursue negotiations toward nuclear disarmament in good faithNew START expiration: what it means and what’s next - ICANicanw .
The disappearance of the last US-Russia treaty without replacement signals the opposite of progress—that major nuclear powers are abandoning restraintThe US and Russia’s nuclear weapons treaty is set to expire. Here’s what’s at stake | Chatham House – International Affairs Think Tankchathamhouse . This creates what arms control experts describe as a "credibility problem for the entire nonproliferation regime"NUCLEAR TREATY EXPIRES TOMORROW — UNLIMITED WARHEADS — ARMS RACE BEGINS — 50 YEARS OVERyoutube . Non-nuclear weapon states will question how they can be lectured about not developing nuclear weapons when the major powers are "expanding your own arsenals and abandoning the treaties that were supposed to limit them"NUCLEAR TREATY EXPIRES TOMORROW — UNLIMITED WARHEADS — ARMS RACE BEGINS — 50 YEARS OVERyoutube .
A joint statement from arms control experts urged both sides to continue observing central limits and resume bilateral talks, emphasizing that "such actions would signal serious implementation of NPT Article VI obligations before the 2026 Review Conference"New START’s Expiration and the Need for Continued Nuclear Restraint : DeepCutsdeepcuts .
In the absence of bilateral treaty constraints, the permanent five nuclear-weapon states (P5) could potentially establish confidence-building measures through multilateral engagement. Chatham House analysts recommend "sustained high-level engagement focused on risk reduction, confidence-building measures and strategic stability" that does not require immediate negotiations on formal limitsThe US and Russia’s nuclear weapons treaty is set to expire. Here’s what’s at stake | Chatham House – International Affairs Think Tankchathamhouse .
Concrete proposals include:
The UK has emphasized that "transparency and dialogue are necessary to prevent or reduce risks of miscalculation and misperception, and thus strengthen stability and reduce risk of unintended nuclear use"Speech: Second Preparatory Committee for the 2026 Review Conference to the Treaty on the Non-Proliferation of Nuclear Weapons: UK statement on Cluster 3 specific issueswww . However, the UK has also expressed regret that "some Nuclear Weapons States do not publish details of their overall warhead stockpiles or on the delivery systems they deploy"—an implicit criticism of China's opacitySecond Preparatory Committee for the 2026 Review Conference to the Treaty on the Non-Proliferation of Nuclear Weapons: UK statement on Cluster 3 specific issuesglobalsecurity .
China's refusal to participate in arms control negotiations represents perhaps the most significant structural obstacle to any successor framework. Beijing maintains that its nuclear forces are "not at all on the same scale as those of the U.S. and Russia" and that it "will not participate in nuclear disarmament negotiations at the current stage"China shuns calls to enter nuclear talks after US-Russia treaty lapses | Northwest & National News | nbcrightnow.comnbcrightnow +1.
China's position rests on several arguments:
However, China's rapid nuclear expansion undermines these arguments. The Stockholm International Peace Research Institute (SIPRI) reports that China's arsenal is "growing faster than any country's, by about 100 new warheads a year since 2023"China shuns calls to enter nuclear talks after US-Russia treaty lapses | Northwest & National News | nbcrightnow.comnbcrightnow . The Pentagon estimates that China could have more than 1,000 operational warheads by the end of the decade and "potentially have at least as many ICBMs as either Russia or the US by the turn of the decade"China is leading the charge to nuclear Armageddon – and Starmer barely noticed | Simon Tisdall | The Guardiantheguardian +1.
Beijing's November 2025 white paper restating its position "conveniently omitted to say" what the minimum level required for national security actually isChina is leading the charge to nuclear Armageddon – and Starmer barely noticed | Simon Tisdall | The Guardiantheguardian . This opacity, combined with rapid expansion, creates the conditions for a three-way arms race that Christine Wormuth, former Secretary of the Army, describes as her "biggest concern".
The erosion of the US-Russia arms control architecture is reshaping the strategic calculations of emerging nuclear powers across multiple regions.
The expiration of New START heightens concerns that renewed arms racing among major powers "could embolden North Korea to expand its nuclear ambitions"Fears mount over N. Korea's arms drive as US-Russia nuclear pact expires - The Korea Timeskoreatimes . Analysts observe that Pyongyang will "more closely watch the shifts in U.S. posture under President Donald Trump on nuclear arms and use the weakening of global arms control norms to further justify its own nuclear program"Fears mount over N. Korea's arms drive as US-Russia nuclear pact expires - The Korea Timeskoreatimes .
Cho Han-bum, senior research fellow at the Korea Institute for National Unification, warns that the erosion of nuclear restraint "could fuel debates over nuclear armament in countries that do not currently possess nuclear weapons, raising concerns about a global 'nuclear domino effect'"Fears mount over N. Korea's arms drive as US-Russia nuclear pact expires - The Korea Timeskoreatimes .
India faces what analysts describe as a "complex strategic challenge" from the erosion of US-Russia arms controlAfter New START: India in a World Where Nuclear ...countercurrents . While never a party to New START or the broader arms control architecture, India "benefited indirectly from the stability such arrangements produced"After New START: India in a World Where Nuclear ...countercurrents .
Key implications for India include:
The weakening of global norms also complicates India's efforts to secure membership in the Nuclear Suppliers Group and liberalize civil nuclear trade, as its case "has rested on its record as a responsible nuclear power adhering to non-proliferation objectives"After New START: India in a World Where Nuclear ...countercurrents .
Pakistan's nuclear posture is undergoing significant organizational transformation under the 27th Constitutional Amendment, which elevates the Chief of Army Staff to Chief of Defense Forces and consolidates nuclear forces under a unified National Strategic CommandThe 27th Amendment and Pakistan’s Emerging Military Posture – The Diplomatthediplomat . This reform marks "the first major change in nuclear force organization since 2000"The 27th Amendment and Pakistan’s Emerging Military Posture – The Diplomatthediplomat .
Pakistan's nuclear strategy also carries regional implications beyond South Asia. A 2025 mutual defense agreement with Saudi Arabia commits both states to defend each other using "all necessary military means"After New START: India in a World Where Nuclear ...countercurrents . In a weakened normative environment, "such language carries nuclear significance" and "extends Pakistan's nuclear logic beyond South Asia and introduces new escalation pathways"After New START: India in a World Where Nuclear ...countercurrents .
Saudi Arabia exhibits characteristics of a "nuclear hedger"—a state laying groundwork for potential weapons pursuitThe Nuclear Kingdom: Assessing Saudi Arabia’s Nuclear Behavior | Georgetown Security Studies Review | Georgetown Universitygeorgetown . Crown Prince Mohammed bin Salman has repeatedly stated that "if Iran developed a nuclear bomb, we will follow suit as soon as possible"Saudi Arabia Said to Produce Ballistic Missiles | Arms Control Associationarmscontrol .
The erosion of arms control norms affects Saudi calculations in several ways:
US lawmakers have warned that "giving Saudi Arabia nuclear technology without the strongest safeguards is a recipe for disaster" and urged gold standard nonproliferation requirements for any 123 agreementCastro, Markey, Colleagues Urge U.S. to Apply Highest Nonproliferation Standards to Any Nuclear Cooperation Agreement with Saudi Arabia Amid Growing Human Rights, National Security Concerns | U.S. Congressman Joaquin Castrohouse .
In East Asia, both Japan and South Korea "possess the technical expertise, industrial infrastructure, and fissile material access required for rapid nuclearization"What Lies Ahead for Nuclear Technology and Security in 2026justsecurity . While neither government has moved toward weaponization, domestic discussions about indigenous deterrent options "have become more politically salient amid North Korea's advancing capabilities and China's expanding nuclear forces"What Lies Ahead for Nuclear Technology and Security in 2026justsecurity .
In Japan, expert debate has "moved from taboo to contingency planning, though public opposition remains substantial." Analysts note that "revising Japan's three non-nuclear principles would establish the groundwork for rapid weaponization should deterrence fail"Asia's nuclear reckoning and the crisis of US deterrence - Asia Timesasiatimes .
South Korea faces a "starker dilemma" given North Korea's designation of South Korea as its principal enemyAsia's nuclear reckoning and the crisis of US deterrence - Asia Timesasiatimes . A South Korean think tank recommends pursuing "arms control diplomacy in coordination with non-nuclear middle powers such as Japan, Australia, Germany, and Canada" while working to establish a multilateral arms control frameworkNew START Expiration Raises Korean Denuclearization Concerns; Think Tank Urges Multilateral Arms Control - Seoul Economic Dailysedaily . Baek Seon-woo of the Institute for National Security Strategy argues that "multilateral systems enable more sustainable arms control" and could be "utilized as a mechanism for managing the North Korean nuclear threat"New START Expiration Raises Korean Denuclearization Concerns; Think Tank Urges Multilateral Arms Control - Seoul Economic Dailysedaily .
Russia's nuclear modernization programs position it to rapidly expand deployed warheads should it choose to do so. Current capabilities include:
Many of Russia's land- and sea-based ballistic missiles are MIRVed but not fully loaded, meaning they could carry additional warheads. With approximately 2,600 nuclear warheads in storage, Russia "could rapidly increase the number of deployed nuclear weapons at its disposal beginning on February 6, 2026"Edging Closer to Armageddon?antiwar .
New systems in development include:
According to the Bulletin of the Atomic Scientists, if Russia decided to exceed New START's central limits, it could "theoretically upload hundreds of warheads onto its deployed delivery systems, potentially increasing its deployed nuclear arsenal by up to 60 percent"Russian nuclear weapons, 2025 - Bulletin of the Atomic Scientiststhebulletin .
The United States is simultaneously undertaking a major nuclear modernization program projected to cost approximately one trillion dollars over the next decadeWhy it matters that the U.S.-Russia New START nuclear treaty expired : NPRnpr . The Trump administration's fiscal year 2026 defense budget request includes:
Department of Energy nuclear weapons programs add another $25 billion, bringing total nuclear-related spending to $87 billion in fiscal 2026Trump Administration Increases Nuclear Weapons Budget - Arms Control Associationarmscontrol . This includes $186 million for the Sea-Launched Cruise Missile-Nuclear (SLCM-N) and $2.6 billion for plutonium pit productionMajority News Release | Majority News Releases | News | United States Senate Committee on Appropriationssenate .
The Union of Concerned Scientists warns that if New START limits are abandoned, "the United States could deploy as many as 3,500 nuclear weapons in a few years" by uploading reserve warheads onto existing delivery systemsNuclear Weapons Without Limits?ucs .
Arms control experts have proposed several options for maintaining strategic stability in the absence of formal treaty limits:
However, prospects for progress remain constrained by the breakdown in US-Russia relations over Ukraine, China's categorical rejection of trilateral negotiations, and the Trump administration's insistence that any future framework must include BeijingStrategic Prudence and Extending New STARTquincyinst +1.
The potential informal observation of New START limits—if confirmed—would represent a politically fragile holding pattern rather than a stable arms control architecture. Without verification mechanisms, such an arrangement depends entirely on political will that could evaporate rapidly, as the SALT II precedent demonstrates.
The broader implications extend far beyond the bilateral relationship. As Chatham House analysts observe, "The removal of any constraints on the US and Russia's nuclear arsenals weakens the argument for restraint elsewhere and reinforces the view that major powers are moving back towards open-ended competition"The US and Russia’s nuclear weapons treaty is set to expire. Here’s what’s at stake | Chatham House – International Affairs Think Tankchathamhouse . From North Korea's justification for continued expansion to Saudi Arabia's hedging strategy to discussions of indigenous deterrents in Japan and South Korea, the erosion of US-Russia arms control is reshaping the strategic calculations of states across the nuclear spectrum.
The period ahead represents what former President Obama described as "pointlessly wip[ing] out decades of diplomacy" with the risk of "spark[ing] another arms race that makes the world less safe"The experts comment: New START expires, bringing both risks and opportunities - Bulletin of the Atomic Scientiststhebulletin . Whether informal restraint can prevent that outcome—and whether new frameworks can emerge from the current diplomatic deadlock—will determine whether the post-New START era becomes an interregnum or a permanent transformation of global nuclear order.