For nearly three decades, the Association of Southeast Asian Nations (ASEAN) has championed the Southeast Asia Nuclear-Weapon-Free Zone Treaty (SEANWFZ), also known as the Bangkok Treaty. Signed in 1995, it commits its 10 member states—Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, the Philippines, Singapore, Thailand, and Vietnam—to ban nuclear weapons from their territories, airspace, and waters while permitting peaceful nuclear energy development. The treaty’s protocol urges the five recognized nuclear powers—China, the US, Russia, the UK, and France—to respect this zone by not deploying or using nukes in the region. On July 7, 2025, Malaysia, ASEAN’s current chair, announced that China had committed to signing the protocol without reservations, a move confirmed by Foreign Minister Mohamad Hasan at a regional forum in Kuala Lumpur. Russia, too, is reportedly on board, though Moscow remains tight-lipped. The US, meanwhile, is playing coy, leaving Southeast Asia wondering if its nuclear-free dream is a diplomatic triumph or a stage for great power posturing.
A Region Caught in the Crosshairs
Southeast Asia is no stranger to being a geopolitical chessboard. Its strategic location—straddling vital maritime routes like the Malacca Strait, through which 60% of global trade flows—makes it a prize for global powers. The South China Sea, a contested hotspot, sees overlapping claims from China, Vietnam, the Philippines, Malaysia, and Brunei, with Beijing’s aggressive island-building and naval patrols raising tensions. Add to that the region’s economic heft: ASEAN’s combined GDP hit $3.6 trillion in 2024, per World Bank data, making it a magnet for influence.
The SEANWFZ treaty emerged from this fraught context. Born in the post-Cold War glow of 1995, it reflected ASEAN’s desire to assert autonomy amid superpower rivalries. The treaty prohibits the development, testing, or stationing of nuclear weapons in the region, while its protocol asks nuclear powers to pledge not to use or threaten nuclear force against ASEAN states. Until recently, none of the five nuclear powers had signed, citing concerns over verification, enforcement, and their own strategic interests. China’s sudden willingness to join, announced in July 2025, has sparked both hope and suspicion, while Russia’s potential involvement and the US’s ambiguity keep the region on edge.
China’s Diplomatic Gambit
China’s pledge to sign the SEANWFZ protocol, as reported by Malaysia’s foreign minister, is a diplomatic coup for Beijing. With an estimated 500 nuclear warheads and plans to reach 1,500 by 2030, per SIPRI’s 2025 report, China is flexing its growing clout. “Beijing’s move is less about disarmament and more about scoring points against the US,” said a Southeast Asia analyst based in Washington. By endorsing SEANWFZ, China paints itself as a responsible regional player, contrasting with the US’s perceived retreat under an erratic foreign policy.
Posts on X reflect the polarized sentiment. One user called China’s commitment “a bold step for regional peace,” while another scoffed, “Believing China on SEANWFZ is like trusting a fox in a henhouse—good luck with that.” The skepticism isn’t baseless. China has been accused of deploying nuclear-powered ballistic missile submarines in the South China Sea, a region the treaty covers. A 2023 Reuters report noted that China keeps at least one such submarine at sea continuously, patrolling from Hainan to disputed waters. The US military also claimed in 2024 that Beijing is eyeing floating nuclear reactors near its artificial islands, potentially violating SEANWFZ’s ban on nuclear weapon transport through the region.
Yet, China’s calculus is clear. “Beijing loses nothing by signing,” a Council on Foreign Relations expert told a German broadcaster. “It’s a low-cost way to burnish its image while the US flounders.” The AUKUS pact—where the US, UK, and Australia are developing nuclear-powered submarines for the Asia-Pacific—gives China a chance to cry foul, pointing to Western hypocrisy. As one Malaysian diplomat put it, “China’s saying, ‘We’re with ASEAN’s vision, while the US brings nukes to your doorstep.’ It’s clever, if not entirely sincere.”
Russia and the US: Will They Follow?
Russia, with the world’s largest nuclear arsenal at 5,580 warheads, per SIPRI, is another key player. Malaysia’s foreign minister hinted that Moscow is ready to sign, following Foreign Minister Sergey Lavrov’s July 2025 visit to Kuala Lumpur. But Russia’s silence raises doubts. Its strategic interests in Southeast Asia, including arms sales to Vietnam and Myanmar, suggest it might see SEANWFZ as a way to counter US influence without sacrificing much. “Russia’s not here to play altruist,” a Singapore-based analyst said. “If they sign, it’s to stick a thumb in Washington’s eye.”
The US, meanwhile, is a wild card. Secretary of State Marco Rubio attended ASEAN talks in July 2025, but Washington has made no commitments. The US has historically balked at SEANWFZ’s protocol, citing concerns over freedom of navigation and the treaty’s vague enforcement mechanisms. With the Trump administration’s “America First” policies sowing uncertainty, Southeast Asia feels the US’s regional clout waning. A 2024 ISEAS-Yusof Ishak Institute survey found that only 29% of Southeast Asian elites see the US as a reliable partner, down from 50% in 2019. “Washington’s distracted, and ASEAN knows it,” a Thai academic noted. “They’re hedging with China and Russia.”
A Fraying Global Order
The SEANWFZ push comes as the rules-based international order frays. The US’s erratic foreign policy, coupled with rising US-China tensions, has left ASEAN states navigating a multipolar world. Russia’s war in Ukraine and China’s assertiveness in the South China Sea underscore the risks of great power rivalry spilling into the region. ASEAN’s response? A delicate balancing act. Countries like Vietnam and Indonesia have deepened ties with Russia and China, with Hanoi signing a $2 billion arms deal with Moscow in 2024 and Jakarta welcoming Chinese infrastructure investments.
The treaty’s revival is partly a reaction to this uncertainty. “ASEAN wants to reassert its centrality,” a Malaysian think-tank researcher said, referencing the bloc’s goal of leading Asia-Pacific diplomacy. But the nuclear powers’ motives are less altruistic. China’s endorsement aligns with its broader strategy to isolate the US, while Russia sees a chance to expand its regional footprint. The US, wary of ceding ground, may sign only if it can extract concessions, like exemptions for its naval operations.
The Limits of a Nuclear-Free Dream
SEANWFZ’s vision carries weight in a region scarred by conflict and colonialism. Malaysia and Indonesia, in particular, have long championed non-proliferation, seeing it as a shield against great power meddling. But the treaty’s effectiveness is questionable. “It’s a noble idea, but nobody’s naive enough to think it’ll stop a nuclear power from doing what it wants,” a Manila-based diplomat said. The treaty lacks robust verification mechanisms, and enforcement relies on goodwill—a scarce commodity in geopolitics.
China’s submarine deployments highlight the gap between rhetoric and reality. The treaty bars signatories from transporting nuclear weapons through the region, yet Beijing’s naval activities suggest it’s already testing those boundaries. The AUKUS pact, which could see nuclear-powered submarines in Australian waters near ASEAN states, further complicates the picture. “ASEAN’s caught between a rock and a hard place,” a Vietnamese scholar said. “We want a nuclear-free zone, but the big players don’t play by our rules.”
What’s at Stake for Southeast Asia?
For ASEAN, SEANWFZ is more than symbolism—it’s a bid for relevance. A nuclear-free zone could deter escalation in the South China Sea and bolster the bloc’s diplomatic clout. Civilian nuclear energy, allowed under the treaty, is also a draw, with Thailand and Vietnam exploring nuclear power plants to meet rising energy demands. But the risks are high. If nuclear powers sign but flout the treaty, ASEAN’s credibility takes a hit. If they don’t sign, the region remains a pawn in their rivalries.
The human stakes are stark. Southeast Asia’s 680 million people live in a region prone to natural disasters and economic volatility. A nuclear incident—accidental or deliberate—would be catastrophic. “We’re not just talking about warheads,” a Bangkok activist said. “Even a reactor mishap could devastate our coasts.” The 2011 Fukushima disaster, which cost Japan $200 billion, looms as a cautionary tale.
A Fragile Hope in a Tense Region
ASEAN’s push to revive SEANWFZ is a bold move in a world where power trumps principle. China’s pledge is a diplomatic win, but its actions in the South China Sea cast a long shadow. Russia’s potential involvement and the US’s indecision add layers of uncertainty. As one Indonesian official put it, “We’re trying to keep the wolves out with a paper fence.” The treaty’s success hinges on trust—something in short supply when nuclear arsenals and geopolitical egos are involved. For now, Southeast Asia’s nuclear-free dream is a flicker of hope in a region bracing for storms, both literal and figurative. As a Cambodian proverb goes, “When elephants fight, it’s the grass that gets trampled.” ASEAN’s just trying to keep the grass alive.
