Why the South China Sea Matters

Clashes between the China Coast Guard and the Philippine Navy escalated in June. Philippine officials announced late last month that Chinese personnel attacked dinghies attempting to provision Philippine troops at the disputed Second Thomas Shoal in the South China Sea.

If China succeeded in dominating the South China Sea, the consequences would be immense: Beijing could potentially choke off trade and shipments to Japan, control access to technologies crucial to U.S. economic activities (especially microchips), and project power deep into the Pacific.

The economic significance of the South China Sea cannot be overstated. As one of the busiest maritime routes in the world, it serves as a vital artery for international trade, facilitating the flow of 64 percent of total goods discharged worldwide in 2022. Any disruption to the free passage of ships through these waters would have far-reaching consequences for the global economy, affecting not only the countries directly involved in the dispute but also the broader international community.

Any attempt by China to restrict access or assert control over the South China Sea would directly impact U.S. economic interests, potentially leading to higher shipping costs, supply chain disruptions, and increased market volatility. South China Sea trade accounts for 5.72 percent of all trade in goods for the United States. Safeguarding freedom of navigation in the South China Sea is essential to protecting American prosperity and maintaining its leadership role in the global economy.

While neighboring countries adhere to their internationally recognized Exclusive Economic Zones (EEZs) for their maritime claims, China asserts sovereignty over a broad swathe of ocean in the South China Sea encompassed by the “nine-dash line.” In 2016, an international tribunal in The Hague ruled against China’s claims, stating that it cannot claim rights to resources in the South China Sea that lie within the EEZs of other coastal states like the Philippines and Vietnam. China rejected the ruling and promptly threatened military force against Vietnam for drilling within its EEZ.

In March of this year, two Philippine naval ships and two coastguard vessels were escorting a civilian boat hired to resupply troops at the Second Thomas Shoal. A Chinese coastguard vessel and two maritime militia vessels encircled the Filipino troops, using water cannons that damaged the civilian boat and harmed crew members. Following several of these encounters, the Philippines has lodged diplomatic protests in Beijing and appealed to the United States for an increased U.S. military presence in the Philippines.

The best way for America to prevent China from seizing control of the South China Sea is to strengthen its own ability to deter China while working with others in the region who feel threatened by the Chinese, including Taiwan, the Philippines, and Vietnam, as well as other states in the broader Indo-Pacific who have an interest in maintaining a free and open South China Sea, like Japan, Australia, South Korea, and India.

The Chinese Communist Party is the odd man out here, pushing for a redefinition of treaties and rebalancing of regional power at the expense of most of its neighbors. The U.S. military’s deterrent effect on the Chinese attempt to establish hegemony in the South China Sea and the Indo-Pacific more generally serves the national security interests of both the United States and the overwhelming majority of countries in the Indo-Pacific.  

Wilson Beaver is a policy advisor for defense budgeting in the Allison Center for National Security at The Heritage Foundation. Find him on X: @WilsonCBeaver.

Maria Victoria Almeida Vazquez was a Spring 2024 Member of the Young Leaders Program at The Heritage Foundation.  

Image: Massimo Todaro / Shutterstock.com.