Nuclear proliferation is the spread and increase of nuclear weapons and technology that has defined international security since the atomic era began in 1945. Due to their catastrophic effects—the ability to knock out entire cities—nuclear weapons posed an existential threat to the global order and arguably became a deterrent to war between major powers.
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As of early 2026, the US and Russia together control about 86% of the world's more than 12,000 nuclear warheads—over 9,600 in military stockpiles. None of the seven other nuclear nations holds more than 600.
Over the Cold War and into the 21st century, US and Soviet/Russian leaders repeatedly agreed to cap arsenals, curb missile deployment, and share ongoing inspections—creating decades of transparency. But in recent years, strained tensions have led to the expiration of arms treaties.
The New START treaty, which capped US and Russian strategic warheads at 1,550 each, expired on February 5, 2026. Without formal limits, fears of a renewed arms race are rising, as both nations could deploy more weapons while follow-on talks continue.
The first use of atomic weapons introduced the possibility of a war with no survivors. This article examines how nuclear fear shaped Cold War diplomacy and continues to influence international relations today.
Worldwide nuclear stockpiles peaked at over 60,000 warheads in the mid‑1980s during the US.–Soviet arms race. Today, about nine nations collectively maintain roughly 12,000 warheads, with Russia and the US still holding the majority.
Nuclear weapons work by unleashing energy from atomic fission—or fusion—reactions. In fission bombs, a critical mass triggers a runaway chain reaction in milliseconds. This video explains the basic science behind their immense explosive power.
China's arsenal grew from an estimated 300 warheads in 2020 to approximately 600 in 2025—making it the world's third-largest nuclear power. The US Department of Defense projects that China will surpass 1,000 warheads by 2030.
The Treaty on the Non‑Proliferation of Nuclear Weapons (created in 1968, effective 1970) binds non-nuclear states to forgo nuclear weapons and commits nuclear powers to share peaceful technology and pursue disarmament—forming the core of the global non-proliferation regime.
Both Russia and the United States have withdrawn from key Cold War-era arms-control pacts. Russia's 2022 invasion of Ukraine marked a turning point, as it suspended its participation in inspections and data-sharing agreements.
The podcast highlights that many of the world's ~12,000 nuclear weapons—capable of triggering global collapse and nuclear winter—remain on high alert. Experts warn that this status, combined with limited public awareness, makes nuclear war disturbingly plausible.
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