The architecture of nuclear arms control between Washington and Moscow that sustained strategic stability for over half a century has largely collapsed. The Intermediate-Range Nuclear Forces Treaty expired in 2019. New START extension negotiations revealed deep structural disagreements about verification regimes and emerging technologies. The bilateral framework that once constrained the world’s two largest nuclear arsenals is operating without reliable institutional guardrails.
The Current Posture
The United States maintains an estimated 5,500 nuclear warheads, while Russia possesses approximately 6,250. Both nations are investing heavily in modernization programs that introduce new delivery systems and complicate traditional counting rules. Russia’s development of hypersonic glide vehicles, nuclear-powered cruise missiles, and unmanned underwater vehicles represents a deliberate strategy to circumvent existing classification frameworks.
American modernization efforts — the B-21 Raider bomber, Columbia-class submarine program, and Ground Based Strategic Deterrent — represent a trillion-dollar investment spread across three decades. These programs were conceived before the current deterioration in bilateral relations but now serve as both deterrent and negotiating leverage.
Verification Challenges
The fundamental challenge facing any successor agreement is verification. Cold War-era treaties relied on national technical means — primarily satellite reconnaissance and signal intelligence — supplemented by on-site inspections. Modern dual-capable systems, which can carry either conventional or nuclear warheads, fundamentally complicate this approach.
Hypersonic weapons present a particular verification challenge. Their ability to carry either nuclear or conventional payloads means that counting rules must address intent as well as capability. Neither side has proposed a workable framework for distinguishing between these configurations during inspection.
Pathways Forward
Three scenarios emerge for the future of US-Russia nuclear relations. The first — a comprehensive successor to New START — would require resolution of fundamental disagreements about what weapons count, how verification occurs, and whether third-party arsenals (particularly China’s) must be included.
The second scenario involves a series of more limited agreements: mutual transparency measures, notification protocols for missile tests, and bilateral risk reduction centers. These confidence-building measures lack the binding force of formal treaties but could establish a foundation for more ambitious negotiations.
The third scenario — continued strategic drift — carries the highest risk. Without institutional frameworks, miscalculation becomes more likely, arms racing proceeds unconstrained, and crisis management depends entirely on ad hoc diplomatic channels that have atrophied since 2022.
Assessment
The probability of a comprehensive successor treaty remains low in the current political environment. The most realistic pathway runs through incremental confidence-building measures that could gradually rebuild the institutional infrastructure necessary for formal negotiations. The window for such measures is narrow, as both nations’ modernization programs approach deployment timelines that will create new facts on the ground.