[Answered] Critically examine the proposition that the actions of a US President could be the catalyst for the demise of the global nuclear order. Analyze its implications for multilateral security.”

Introduction

Despite nuclear arsenals reducing from 65,000 in the 1970s to 12,500 today (SIPRI 2024), recent U.S. signals of resuming nuclear testing threaten to erode long-standing norms, rekindling uncertainties in global nuclear governance.

Why Presidential Decisions in the U.S. Matter for the Global Nuclear Order

1. The U.S. as an Architect of the Nuclear Regime: The United States shaped the NPT (1968), led the push for the CTBT (1996), and negotiated major arms-control treaties such as INF (1987) and New START (2010). Because the U.S. is a nuclear superpower and norm-setter, any deviation from restraint signals a systemic shift.
2. Resumption of Nuclear Testing: A Normative Shock: Donald Trump’s 2025 announcement to “start testing our nuclear weapons” risks: Breaking the moratorium since 1992, Undermining the global taboo on nuclear explosive tests and Encouraging Russia, China, India, Pakistan, and North Korea to follow suit. The CTBT, although not in force, functions as a de facto global norm. Its collapse would dismantle verification structures like the International Monitoring System (IMS).
3. Acceleration of a New Arms Race: Presidential encouragement of testing or arms development heightens instability by incentivising states to pursue new warhead designs, hypersonic glide vehicles, and MIRV capabilities. Even before Trump’s announcement, an incipient arms race existed: Russia tested the nuclear-powered Burevestnik cruise missile and Poseidon underwater drone, China is rapidly expanding warheads (projected 1,000 by 2030) and U.S. began deploying low-yield warheads (W76-2) and new B61-13 bombs

• Collapse of Arms-Control Architecture: Trump’s stance threatens the last remaining pillar of U.S.–Russia nuclear stability. The absence of arms-control transparency increases risks of miscalculation, first-strike anxieties, and accidental escalation. U.S. actions since 2018 already weakened the system: Withdrawal from INF Treaty, Uncertainty over Open Skies Treaty and Minimal progress on New START extension, expiring February 2026

Implications for Multilateral Security

1. Erosion of Non-Proliferation Norms: A U.S. return to nuclear tests could trigger: Indian and Pakistani renewed testing (India has tested thermonuclear designs only once) Middle Eastern states revisiting latent nuclear programmes (Iran, Saudi Arabia). Growing disenchantment with NPT inequities, pushing states toward hedging.
2. Rise of Regional Nuclear Instabilities

• East Asia: Japan and South Korea may reconsider nuclear latency as China expands arsenal
• West Asia: An already fragile Iran nuclear situation may worsen
• South Asia: India-Pakistan deterrence stability becomes more volatile

3. Undermining UN-based Collective Security: The UN Secretary-General warns that nuclear risks are at “alarmingly high levels.” If U.S. leadership recedes, multilateral forums like the UNSC, IAEA, and NPT Review Conferences lose coherence.
4. Weakening of the “Nuclear Taboo”: Political signalling by a U.S. President that normalises nuclear usability (low-yield warheads, dual-use hypersonics) erodes the moral restraint described by scholars like Nina Tannenwald.

Conclusion

Nuclear stability hinges on credible restraint. U.S. destabilisation risks unraveling global norms, making multilateral security arrangements dangerously fragile amid emerging geopolitical fractures.