China’s control over the South China Sea is far from guaranteed, according to a detailed analysis by experts at Chatham House. Despite Beijing’s formidable naval power and increasing technological integration with Southeast Asian economies, a coordinated and pragmatic response from regional states and their partners could still prevent China from fully dominating these contested waters.

China’s growing dominance in the South China Sea has been widely accepted by many as inevitable, given its vast economic influence, technological advancements, and expanding maritime presence. However, a recent report by Ben Bland and William Matthews of Chatham House challenges this narrative. Drawing on consultations with policymakers and experts from both Southeast Asia and the United Kingdom, the study concludes that the trajectory of Chinese control is not set in stone, and there remain realistic strategies to curb Beijing’s ambitions without escalating into direct conflict.

The Chatham House analysis underscores how Beijing’s influence in the region is being reinforced not just through its military expansion—marked by artificial islands, fortified bases, and an increasingly assertive navy—but through a comprehensive strategy blending economic entanglement and technological dominance. China’s investments across Southeast Asia in infrastructure, renewable energy, digital technologies, and emerging sectors like AI have created a web of dependencies that weakens the region’s collective ability to resist maritime coercion.

Beijing’s grip is tightening as it integrates Southeast Asian economies deeper into its manufacturing and technological networks. Chinese companies are heavily invested in key industries across the region, from Indonesia’s burgeoning tech sector to Malaysia’s renewable energy projects. This economic entanglement makes countries less willing to challenge China over its assertive actions in the South China Sea, fearing repercussions that could harm their access to investment, technology, and trade.

The report emphasizes that Southeast Asia’s heavy reliance on Chinese technology and its integration into digital infrastructure and energy supply chains pose long-term risks to regional sovereignty. As Beijing continues to lead in sectors such as solar energy, battery production, and AI, its leverage grows. China’s ability to offer affordable and advanced solutions strengthens its position as an indispensable partner, discouraging governments from taking a firm stance against its maritime ambitions.

Despite these pressures, the authors argue that Southeast Asian nations are not without options. They highlight the importance of diversifying economic relationships through platforms like the Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP) and strengthening ties with countries like Japan, Australia, South Korea, and the European Union. Such diversification could reduce vulnerability to Chinese coercion by opening alternative markets for trade, technology, and investment.

Military deterrence also plays a role, though the focus should not be on matching China’s navy ship-for-ship. Instead, Southeast Asian states could enhance their security through cost-effective investments in maritime surveillance, unmanned systems, and autonomous patrol technologies. Supported by external partners, these measures would help monitor and resist gray-zone tactics without provoking direct military confrontation.

However, the report warns that ASEAN’s institutional weaknesses and internal divisions undermine any collective response. The bloc’s failure to present a unified front allows China to continue its incremental encroachments unchallenged. This lack of cohesion further emboldens Beijing’s strategy of exploiting divisions to weaken opposition to its maritime claims.

Legal approaches, such as appeals to international tribunals, are acknowledged as having limited effect. While these rulings bolster the legal rights of claimant states, they have not deterred China’s actions, which continue despite global condemnation. Real deterrence, the report argues, will come from practical measures and robust alliances, not from courtrooms alone.

The Chatham House experts caution that inaction carries risks not just for Southeast Asia but for the broader international community. If China solidifies control over these waters, it could extend similar strategies to other contested maritime regions, threatening freedom of navigation and undermining international norms. Countries beyond the region have a vested interest in supporting efforts to maintain an open and contested South China Sea.

Ultimately, the report concludes that while Beijing’s dominance is a serious threat, it is not inevitable. Through strategic diversification, enhanced maritime capabilities, and strengthened alliances, Southeast Asian nations can retain agency over their future. The key is pragmatic action to prevent further entrenchment of Chinese influence before it becomes irreversible.