[Video] Is the world entering a more dangerous nuclear era?

A fragile nuclear order is slipping further into uncertainty, reviving fears of heightened great power tensions and a renewed arms race. On 5 February 2026, the New START treaty expired, ending the last legally binding US–Russia framework that limited strategic nuclear arsenals and provided verification-based transparency. The collapse of these constraints has heightened concerns over stability. US President Donald Trump had sought to bring China into future nuclear arms control talks, but Beijing has declined, arguing it is not on the same nuclear level as the US and Russia.

As of 2025, the US holds roughly 3,700 warheads, with about 1,700 deployed. Russia’s stockpile exceeds the US by approximately 2,000, although deployed numbers remain similar. Both powers are rapidly modernising their nuclear triads. China, with an estimated 600 warheads, continues to follow a “minimum deterrence” strategy under frameworks such as the Treaty on the Non-Proliferation of Nuclear Weapons (NPT).

Despite growing concerns, a near-term arms race or nuclear escalation remains unlikely. Robert S. Ross, a professor of political science at Boston College, notes that neither the US nor Russia currently possesses the technology or equipment to undertake a rapid build-up. Doctrines such as Mutually Assured Destruction (MAD), which rely on second‑strike capability to deter nuclear use, still act as stabilising constraints.

Risks, however, are evolving. The absence of verification mechanisms increases the risk of miscalculation. Emerging technologies such as hypersonic weapons compress decision times and blur the distinction between conventional and nuclear threats, intensifying strategic uncertainty and challenging traditional deterrence frameworks.

The implications of a world without formal nuclear limits extend beyond the superpowers. In the Middle East, Iran, thought of as a nuclear threshold state before US attacks on facilities last year, could be rebuilding and moving closer to nuclear capability amid growing distrust of the US and Israel and the rising influence of hardliners. The current Iran war, albeit under a fragile truce, provides greater uncertainty and impetus.

Iran could either develop a nuclear weapon independently, whether a “dirty bomb” or a traditional one, or receive foreign assistance, possibly from North Korea, though this is less likely. Nonetheless, the near-term risk of a deployable Iranian weapon remains low. More likely, Gulf states will strengthen security partnerships, enhance missile defences and pursue collective defence arrangements, such as the recent Saudi-Pakistan treaty, hedging against threats without triggering a regional nuclear arms race, says Hao Nan, a Nuclear Futures fellow (2025-2026) with the Ploughshares Fund & Horizon 2045.

In East Asia, the Korean peninsula continues to be a key flashpoint. North Korea’s advancing nuclear capabilities, coupled with an intensifying US-China rivalry, place South Korea in a persistent strategic dilemma. South Korea relies on US security guarantees but fears being drawn into great power conflict. Domestic support for an independent nuclear option has grown, reflecting doubts about extended deterrence.

In practice, however, South Korea is tightly constrained by its alliance with the US, lacking the strategic space, technical capabilities and testing grounds to pursue an independent programme. Any unilateral move would provoke strong opposition from major powers and threaten the alliance that underpins its security. Instead, it is exploring pragmatic alternatives, such as strengthening military capabilities through US-backed nuclear-powered submarines. For now, tensions are easing, but the threat of escalation remains.

Much of it will depend on the role that the great power politics and the US will play in the regions. While the absence of direct rivalry can reduce proxy conflicts, local tensions may still escalate if major powers withdraw influence. Great collaboration among great powers, however, can help contain disputes, as seen in the recent Cambodia-Thailand conflict where US and Chinese pressure helped prevent escalation. Avoiding war and managing local conflicts remain central responsibilities for major powers in order to maintain global stability.

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