SIPRI 2025 Report: Nuclear Modernization and Global Risks

Why in news? The Stockholm International Peace Research Institute (SIPRI) in its 2025 Yearbook reports that nearly all nine nuclear-armed states—the United States, Russia, the United Kingdom, France, China, India, Pakistan, North Korea, and Israel—continued intensive nuclear modernization programs in 2024.

Key Findings:

• Global Nuclear Inventory: As of January 2025, the global nuclear warhead inventory is estimated at 12,241, with 9,614 in military stockpiles for potential use. Approximately 3,912 warheads are deployed with missiles and aircraft, and around 2,100 are on high operational alert, primarily held by Russia and the USA, with China possibly maintaining some warheads on alert during peacetime.
• India’s Nuclear Arsenal: India slightly expanded its nuclear stockpile from 172 warheads in January 2024 to 180 in January 2025.
• Pakistan’s Developments: Pakistan’s nuclear arsenal remained stable at 170 warheads in January 2025. However, it continued to develop new delivery systems and accumulate fissile material, suggesting potential arsenal expansion over the next decade. Pakistan’s doctrine emphasizes short-range tactical nuclear weapons, which SIPRI notes could lower the threshold for nuclear use, increasing regional instability.

Other Nuclear Powers:

United States: Holds 5,177 warheads (1,770 deployed, 1,930 stored), down from 5,328 in 2024. Its modernization program faces funding and planning challenges but continues to progress.

Russia: Possesses 5,459 warheads (1,718 deployed, 2,591 stored), reduced from 5,580 in 2024. It is modernizing its arsenal, with potential increases in deployed warheads post-New START expiry.

China: Expanded its arsenal to 600 warheads (24 deployed, 576 stored) from 500 in 2024, the fastest growth among nuclear powers. It completed around 350 new ICBM silos by January 2025.

Other States: The UK, France, Israel, and North Korea are also modernizing their arsenals, with North Korea estimated to have assembled around 50 warheads and Israel upgrading its plutonium production capabilities.

Regional and Global Implications:

• The SIPRI report warns that the modernization and expansion of nuclear arsenals, particularly in South Asia, heighten the risk of escalation. India’s adoption of canisterized missiles and a potential shift toward mating warheads with launchers during peacetime could reduce response times, increasing the chance of miscalculation.
• Pakistan’s focus on tactical nuclear weapons further destabilizes the region, as their battlefield use could trigger rapid escalation.
• The brief India-Pakistan conflict in early 2025 underscores the fragility of nuclear deterrence in the region, exacerbated by disinformation and strikes on sensitive military sites. Globally, the report notes that the post-Cold War trend of reducing nuclear stockpiles is likely to reverse as dismantlement slows and new deployments accelerate.

Key Features of the New START Treaty:

Limits on Strategic Nuclear Weapons:

1. • Each country is allowed a maximum of 1,550 deployed nuclear warheads.
   • The number of deployed intercontinental ballistic missiles (ICBMs), submarine-launched ballistic missiles (SLBMs), and heavy bombers equipped for nuclear weapons is capped at 700.
   • A further limit of 800 is placed on deployed and non-deployed launchers.

Reduction in Global Nuclear Risks:

1. • It builds on previous treaties like START I (1991) and SORT (Moscow Treaty, 2002), furthering efforts to reduce nuclear stockpiles.