The Stockholm International Peace Research Institute (SIPRI) has issued a stark warning that the world is entering a new nuclear arms race, reversing decades of nuclear disarmament and significantly escalating global risk .
As of January 2025, there were an estimated 12,241 nuclear warheads in existence, with 9,614 held in military stockpiles and 2,100 kept on high alert—nearly all by the U.S. and Russia.
SIPRI’s Yearbook 2025 reports that all nine nuclear-armed states are now expanding or modernizing their arsenals.
Key insights from SIPRI’s analysis include:
Resurgence of arsenals: The post‑Cold War downtrend in nuclear stockpiles is rapidly eroding. SIPRI says “the era of reductions … is coming to an end”.
U.S. and Russian modernization: While warhead totals remained stable in 2024, both countries are conducting massive modernization campaigns that may increase their deployed arsenals after New START expires in 2026.
China’s rapid buildup: With around 600 warheads, China is adding approximately 100 warheads per year and constructing 350 new ICBM silos—potentially matching U.S./Russian missile capabilities by 2030.
Rising modernization: India, Pakistan, North Korea, the UK, France, and Israel are also upgrading nuclear and delivery systems, with deployment on missiles becoming more common.
SIPRI Director Dan Smith highlighted that new technologies—including artificial intelligence, cyber tools, and space-based platforms—are redefining the nuclear battlefield and increasing the risk of miscalculation and accidental escalation.
