The End of an Era: New START Treaty Expires, Removing Last Limits on US and Russian Nuclear Arsenals

On Thursday, February 5, 2026, the New Strategic Arms Reduction Treaty (New START or SNV-III) officially reached its expiration date. This landmark agreement represented the final legally binding mechanism regulating the strategic nuclear stockpiles of both the Russian Federation and the United States of America. For years, this document served as a cornerstone of global stability, but its conclusion now leaves the world’s two largest nuclear powers without any formal constraints on a potential arms race.

This development marks a significant rupture in over half a century of traditional arms control, ushering international security into a volatile era of unregulated strategic competition. Originally signed in Prague on April 8, 2010, the treaty went into effect on February 5, 2011. It established strict ceilings for both nations, limiting each side to 1,550 deployed strategic warheads and a combined total of 800 deployed and non-deployed launchers.

On the eve of the expiration, February 4, Russian officials stated that they no longer consider themselves bound by any New START obligations. This announcement followed what Moscow described as a lack of formal response from Washington regarding a proposal for a one-year voluntary adherence to the treaty's core quantitative limits. Dmitry Medvedev, the Deputy Chairman of the Security Council of the Russian Federation, noted that while Russia is prepared to implement military-technical countermeasures to ensure its security, it remains open to a dialogue based on equality and does not intend to be drawn into a reckless arms race.

The treaty's verification regime was a vital component for maintaining predictability and minimizing the risk of strategic miscalculations. This system included on-site inspections and a consistent exchange of data, though physical inspections had been on hiatus since 2023. According to the U.S. State Department, the absence of these measures significantly diminishes intelligence regarding Russian nuclear capabilities, specifically involving Intercontinental Ballistic Missiles (ICBMs), Submarine-Launched Ballistic Missiles (SLBMs), and heavy bombers.

Diplomatic efforts to save the agreement had surfaced as recently as September 2025, when President Vladimir Putin suggested a one-year extension of the quantitative caps. This proposal was contingent on the United States refraining from actions that might destabilize the balance of deterrence, such as the deployment of the "Golden Dome" missile defense system. While Donald Trump, who assumed the U.S. presidency in January 2025, initially showed a positive reaction to the idea, no formal consensus or signed agreement ever materialized.

Historically, the New START framework was never viewed as perfect by either Moscow or Washington, with both parties harboring specific grievances over the years. Nevertheless, the treaty was the product of significant compromises that prioritized global safety. Now, with bilateral relations deteriorated to a point where mutual concessions are no longer feasible, the treaty has simply been allowed to lapse. This creates a dangerous vacuum where a lack of transparency regarding an adversary's arsenal size and readiness can lead to catastrophic errors in military planning and the potential deployment of strategic forces.

The geopolitical landscape is further complicated by the stance of Beijing, which has consistently rejected invitations to join trilateral nuclear negotiations despite repeated calls from President Trump. Lin Jian, a spokesperson for the Chinese Ministry of Foreign Affairs, argued that China’s nuclear capabilities exist at a fundamentally different level than those of the U.S. or Russia, calling demands for their inclusion "unjust and unreasonable." Analysts now warn of a destabilizing three-way arms race involving the U.S., Russia, and China, potentially mirroring the tensions of the Cold War era.

While the United States and Russia still command more than 80% of the world's nuclear warheads, SIPRI estimates indicate that China’s arsenal is expanding more rapidly than any other, having reached at least 600 warheads. The expiration of New START, which originally replaced the 2002 Strategic Offensive Reductions Treaty (SORT), threatens the entire architecture of international arms control that began with the SALT-I Treaty in 1972. Without a successor, the global community faces an uncertain future regarding nuclear restraint.