NUCLEAR ORDER IN DECLINE: UNDERSTANDING THE DRIVERS OF U.S.–RUSSIA ARMS CONTROL FAILURE

Abstract

This study examines the growing fragility of strategic stability between the United States and Russia in the aftermath of the collapse of key arms-control agreements. Since the end of the Cold War, both states have framed stability as a central objective of their foreign and defense policies, yet the past decade has witnessed accelerated military modernization, deepening geopolitical mistrust, and the erosion of longstanding restraints. The U.S. withdrawal from the Intermediate-Range Nuclear Forces Treaty and Russia’s suspension of New START—now approaching its expiration in 2026—have left the world’s two largest nuclear powers without a functioning framework to manage their rivalry. Attempts at diplomatic revival since 2025 briefly raised hopes, but the ongoing war in Ukraine, NATO–Russia tensions, and domestic skepticism toward arms control in both capitals have halted progress. Drawing on recent developments, including the modernization of nuclear arsenals, the deterioration of compliance mechanisms, and shifting threat perceptions, this study argues that the U.S. and Russia are re-entering an action–reaction spiral which is explained by two-level games, proposed by Robert Putnam in 1988. The continuous hostility between US and Russia risks triggering new missile deployments in Europe, further weakening the global arms-control regime. All these facets along with risks and uncertainties involved in arms race will be discussed in this study. The study will also assess whether US and Russia can develop a framework for non-treaty options which both countries can mitigate in order to develop a working relation.