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South China Sea

The South China Sea is a strategically significant area in the western Pacific Ocean, bordered by nations such as China, Taiwan, Vietnam, the Philippines, and Malaysia, all of which have competing territorial claims over its islands and waters. This sea is crucial for global shipping, with about one-third of the world’s maritime trade passing through it, and is rich in fishing resources and untapped oil and natural gas deposits. The region has seen increasing tensions and military confrontations, particularly between China and the United States, the latter being an ally of several Southeast Asian nations. The South China Sea is home to around 250 islands, reefs, and atolls, with ownership of these features often disputed, exacerbating local and international conflicts. Since the early 2000s, China has sought to assert its claims, including militarization of artificial islands, leading to heightened geopolitical friction. The area is not only a focal point for national interests but also a site of international diplomacy, drawing attention from organizations like ASEAN and the United Nations. Ongoing incidents, such as confrontations between naval forces and issues involving fishing rights, continue to dominate the regional landscape, raising concerns about potential miscalculations that could escalate into larger conflicts.

Full Article

The South China Sea is located in the western part of the Pacific Ocean and primarily bordered by China, Taiwan, Vietnam, Cambodia, the Philippines, Malaysia, and Indonesia; many of these countries have conflicting claims on islands and ocean areas within the sea. By the early 2020s, roughly one-third of global shipping passed through the South China Sea, and the area had become an area of dispute among some of its bordering nations. The primarily issues center on control of the sea's shipping lanes, rich fishing waters, and huge oil and natural gas deposits. The South China Sea is home to roughly 250 disputed islands, atolls, reefs, and sandbars. Violent confrontations have taken place in the region, including standoffs between the naval forces of China and the Philippines, and China and the United States—a key ally of the Philippines and Taiwan. Political tensions run high in the region, dominating the agendas of the Association of Southeast Asian Nations (ASEAN), and United Nations councils and committees in the twenty-first century.

Background

The South China Sea first became popular as another trade route linking Europe, Asia, India, and the Middle East, complementing the overland Silk Road. The people bordering the sea excelled at ship building, shipping, and goods trading. The expanding trade demanded larger, more seaworthy ships than the Chinese junk. New ships were made to carry more goods and be able to traverse greater distances. By the Middle Ages, the mid-1500s, shipbuilding yards were thriving in Japan and in China on the Yangtze near Nanking. Builders excelled in developing new techniques preventing wood rot and technical developments building ships seventy meters long, able to carry two thousand tons of goods, with storage capacity for the sails needed to power the full ships over long distances.

World War II (1939–45), as well as the decolonization of Vietnam, the Philippines, and other countries in the area, greatly altered the balance of power in the region. The sea was critical to the Japanese invasion of China and Southeast Asia during the 1930s. It became a military theater between the Allies and Axis powers as part of the Pacific Theater of World War II. After the war ended in 1945 with the defeat of the Japanese Empire and Nazi Germany, Western democracies stationed naval ships and built ports and military bases on the sea. The United States and its allies wanted to contain the China’s Communist government, which had taken over the country in 1949 under the leadership of Mao Zedong, from subsuming Taiwan, Hong Kong, the Philippines, South Korea, Vietnam, Thailand, and other nations.

The nations bordering the sea and the superpowers were able to maintain a relative state of maritime peace and order through international negotiated agreements. China's economy grew significantly during the second half of the twentieth century, turning the country into an economic powerhouse, which affected its need for open access and control of shipping lanes and the world’s largest oil consumer, sparking tensions in the region. Ongoing tensions between Taiwan and China over the political status of Taiwan further complicated the situation.

South China Sea Today

Beginning in 2000, China began establishing and attempting to assert sovereignty over islands in the sea, contributing to tensions in the region. The Philippines and South Korea harassed Chinese flagged boats in 2011. The United States also sought to preserve open access in the South China Sea. Its navy held maneuvers, sometimes coordinating with militaries from China’s neighbors, to assert US economic and geopolitical interests.

By 2016, the United States was siding with many ASEAN members, demanding that China respect others’ claims under international law. In addition to the heavy shipping lanes—three times greater than those of the Suez Canal at that time—and oil and gas deposits, 8 percent of the world’s fish catches came from the South China Sea. Indonesia adopted the policy of destroying fishing vessels from foreign nations like Vietnam and the Philippines. China intervened in 2006 when Indonesia detained one of its fishing boats, raising tensions to an international incident. The Chinese navy threatened military ships from India; following this incident, India and Vietnam announced in 2011 agreements for joint exploration of the natural resources of the South China Sea. China vehemently objected to these agreements.

The United States and allies raised issues about Chinese military aggression in the South China Sea, while China countered that it was simply asserting its own sovereignty. The Chinese government responded, in part, by deploying two naval destroyers, two frigates, and a supply ship into the South China Sea in May 2016 for comprehensive combat drills in response to US naval deployments and strengthening diplomatic and military ties with China’s rival neighbors. This contributed to a growing fear among world leaders that despite economic ties between the United States and China, miscalculations, acts of unilateral aggression, or just plain mistakes could spark violent confrontations that could grow out of control. In 2009, a Chinese submarine collided with an American destroyer, highlighting the possibility of dangerous accidents that could be misinterpreted. Chinese aircraft and ships are increasing their harassment of US intelligence and surveillance aircraft and ships in the sea. Exacerbating the tensions is China’s construction of artificial islands for military purposes in the South China Sea hundreds of miles off China’s coast. Other countries are getting into the act. In 2014, for example, Taiwan spent $100 million in the South China Sea to build airplane and ship facilities.

The buildup of the Chinese military in the South China Sea that began in the 2010s continued into the next decade. In 2022, the United States Navy said that China had armed its artificial islands, which are positioned in key areas of the South China Sea, with antiship and antiair missiles and jamming equipment intended to deter and disrupt foreign operations in the sea. By that time, the US estimated that China had militarized at least three islands. The US Navy considered China's military buildup in the South China Sea to be the largest amassing of military assets in the area since World War II. The islands, which were equipped with airfields and other key military infrastructure, operated as staging areas that allow the Chinese military to exert its influence in the South China Sea far beyond what the previous mainland bases allowed.

Other incidents throughout the early 2020s ensured that tensions remained high in the South China Sea. At that time, China claimed sovereignty over 90 percent of the sea's area, a claim that infringed on the exclusive economic zones (EEZs) of Vietnam, Malaysia, Brunei, Indonesia, and the Philippines. The navies of the US and China continued to confront each other periodically, leading to occasional close calls. For example, in October 2023, a Chinese fighter jet allegedly flew within ten feet of a US bomber.

Tensions between China and the Philippines have grown particularly acute since 2023. Repeated confrontations at strategic locations such as the Second Thomas Shoal and Scarborough Shoal have included aggressive maneuvers such as the use of water cannons, dangerous blocking, and even laser pointing. In February 2023, a China Coast Guard vessel aimed a “military-grade” laser at the Philippine patrol ship BRP Malapascua during a resupply mission—an act that the Philippine government formally protested as a deliberate and dangerous provocation. In August of the same year, Chinese vessels engaged in water-cannon harassment and risky maneuvers while attempting to block Philippine resupply boats near Second Thomas Shoal.

Tensions escalated further in June 2024 when the China Coast Guard interfered with another Philippine resupply mission, with reports of boarding, injuries, equipment damage, and confiscation of firearms. The Philippines has responded by steadily strengthened its defense posture. It has markedly deepened security ties with the United States through expanded joint patrols and exercises, including air and maritime drills over the South China Sea in May 2025. At that time, the Philippines and the United States held their first joint maritime drills involving both coast guards, navies, and air forces in the South China Sea, near Palawan and Occidental Mindoro. The exercises, which included communication and search-and-rescue drills, were the second such activity in 2025 and the sixth since joint operations began in 2023. The drills aimed to improve cooperation and strengthen defense ties as tensions with China over territorial disputes continued in the region.

The Philippines has also amplified its military collaboration with other allies, including planned defense agreements with Australia. Philippine Defense Secretary Gilberto Teodoro said the new defense pact would allow more frequent joint military drills to improve cooperation and strengthen regional security.


Bibliography

Flores, Mikhail. "Philippines, Australia to Seal New Defence Pact as China Tensions Rise ." Reuters, 22 Aug. 2025, www.reuters.com/world/china/philippines-australia-seal-new-defence-pact-china-tensions-rise-2025-08-22/. Accessed 22 Aug. 2025.

Friar, Karen. "China’s artificial islands in before-and-after photos." Market Watch, 4 Jan. 2016, www.marketwatch.com/story/chinas-artificial-islands-in-before-and-after-photos-2015-10-27. Accessed 8 Apr. 2022.

Holt, Sean M. "Five Countries, Other Than China, Most Dependent on the South China Sea." CNBC, 17 Nov. 2022, www.cnbc.com/2022/11/18/five-countries-other-than-china-most-dependent-on-the-south-china-sea.html. Accessed 25 Mar. 2024.

Huang, J., and Andrew Billo, eds. Territorial Disputes in the South China Sea: Navigating Rough Waters. Palgrave MacMillan, 2015.

Jung, Ann. "ASEAN and the South China Sea: Deepening Division." The National Bureau of Asian Research, 16 July 2012, www.nbr.org/publication/asean-and-the-south-china-sea-deepening-divisions/. Accessed 8 Apr. 2022.

Manguin, Pierre-Yves. "Trading Ships of the South China Sea." Journal of the Economic and Social History of the Orient, 36.3 (1993): 253-80, search.ebscohost.com/login.aspx?direct=true&db=edsjsr&AN=edsjsr.10.2307.3632633&site=eds-live. Accessed 8 Apr. 2022.

"Philippines Removes South China Sea 'Floating Barrier' Installed by China." Al Jazeera, 25 Sept. 2023, www.aljazeera.com/news/2023/9/25/china-defends-south-china-sea-floating-barrier-as-manila-vows-to-remove. Accessed 25 Mar. 2024.

"Philippines, U.S. Hold Joint Maritime Drills in South China Sea ." Reuters, 20 May 2025, www.reuters.com/world/china/philippines-us-hold-joint-maritime-drills-south-china-sea-2025-05-21/. Accessed 22 Aug. 2025.

Shankar, Sneha. "Taiwan to Build $100M Port in Disputed Region of the South China Sea but China Does Not React." International Business Times, 26 May 2014, www.ibtimes.com/taiwan-build-100m-port-disputed-region-south-china-sea-china-does-not-react-1590010. Accessed 12 Apr. 2022.

Shen, Jianming. "China’s Sovereignty over the South China Sea Islands: A Historical Perspective." Chinese Journal of International Law, vol 1, no. 1, 2002, pp. 94-157, academic.oup.com/chinesejil/article/1/1/94/362104. Accessed 11 Apr. 2022.

Zhen, Liu. "Chinese Naval Group Heads to Disputed South China Sea for Combat Drill." South China Morning Post, 6 May 2016, www.cnbc.com/2016/05/05/chinese-naval-group-heads-to-disputed-south-china-sea-for-combat-drill.html. Accessed 11 Apr. 2022.


Full Article

The South China Sea is located in the western part of the Pacific Ocean and primarily bordered by China, Taiwan, Vietnam, Cambodia, the Philippines, Malaysia, and Indonesia; many of these countries have conflicting claims on islands and ocean areas within the sea. By the early 2020s, roughly one-third of global shipping passed through the South China Sea, and the area had become an area of dispute among some of its bordering nations. The primarily issues center on control of the sea's shipping lanes, rich fishing waters, and huge oil and natural gas deposits. The South China Sea is home to roughly 250 disputed islands, atolls, reefs, and sandbars. Violent confrontations have taken place in the region, including standoffs between the naval forces of China and the Philippines, and China and the United States—a key ally of the Philippines and Taiwan. Political tensions run high in the region, dominating the agendas of the Association of Southeast Asian Nations (ASEAN), and United Nations councils and committees in the twenty-first century.

Background

The South China Sea first became popular as another trade route linking Europe, Asia, India, and the Middle East, complementing the overland Silk Road. The people bordering the sea excelled at ship building, shipping, and goods trading. The expanding trade demanded larger, more seaworthy ships than the Chinese junk. New ships were made to carry more goods and be able to traverse greater distances. By the Middle Ages, the mid-1500s, shipbuilding yards were thriving in Japan and in China on the Yangtze near Nanking. Builders excelled in developing new techniques preventing wood rot and technical developments building ships seventy meters long, able to carry two thousand tons of goods, with storage capacity for the sails needed to power the full ships over long distances.

World War II (1939–45), as well as the decolonization of Vietnam, the Philippines, and other countries in the area, greatly altered the balance of power in the region. The sea was critical to the Japanese invasion of China and Southeast Asia during the 1930s. It became a military theater between the Allies and Axis powers as part of the Pacific Theater of World War II. After the war ended in 1945 with the defeat of the Japanese Empire and Nazi Germany, Western democracies stationed naval ships and built ports and military bases on the sea. The United States and its allies wanted to contain the China’s Communist government, which had taken over the country in 1949 under the leadership of Mao Zedong, from subsuming Taiwan, Hong Kong, the Philippines, South Korea, Vietnam, Thailand, and other nations.

The nations bordering the sea and the superpowers were able to maintain a relative state of maritime peace and order through international negotiated agreements. China's economy grew significantly during the second half of the twentieth century, turning the country into an economic powerhouse, which affected its need for open access and control of shipping lanes and the world’s largest oil consumer, sparking tensions in the region. Ongoing tensions between Taiwan and China over the political status of Taiwan further complicated the situation.

South China Sea Today

Beginning in 2000, China began establishing and attempting to assert sovereignty over islands in the sea, contributing to tensions in the region. The Philippines and South Korea harassed Chinese flagged boats in 2011. The United States also sought to preserve open access in the South China Sea. Its navy held maneuvers, sometimes coordinating with militaries from China’s neighbors, to assert US economic and geopolitical interests.

By 2016, the United States was siding with many ASEAN members, demanding that China respect others’ claims under international law. In addition to the heavy shipping lanes—three times greater than those of the Suez Canal at that time—and oil and gas deposits, 8 percent of the world’s fish catches came from the South China Sea. Indonesia adopted the policy of destroying fishing vessels from foreign nations like Vietnam and the Philippines. China intervened in 2006 when Indonesia detained one of its fishing boats, raising tensions to an international incident. The Chinese navy threatened military ships from India; following this incident, India and Vietnam announced in 2011 agreements for joint exploration of the natural resources of the South China Sea. China vehemently objected to these agreements.

The United States and allies raised issues about Chinese military aggression in the South China Sea, while China countered that it was simply asserting its own sovereignty. The Chinese government responded, in part, by deploying two naval destroyers, two frigates, and a supply ship into the South China Sea in May 2016 for comprehensive combat drills in response to US naval deployments and strengthening diplomatic and military ties with China’s rival neighbors. This contributed to a growing fear among world leaders that despite economic ties between the United States and China, miscalculations, acts of unilateral aggression, or just plain mistakes could spark violent confrontations that could grow out of control. In 2009, a Chinese submarine collided with an American destroyer, highlighting the possibility of dangerous accidents that could be misinterpreted. Chinese aircraft and ships are increasing their harassment of US intelligence and surveillance aircraft and ships in the sea. Exacerbating the tensions is China’s construction of artificial islands for military purposes in the South China Sea hundreds of miles off China’s coast. Other countries are getting into the act. In 2014, for example, Taiwan spent $100 million in the South China Sea to build airplane and ship facilities.

The buildup of the Chinese military in the South China Sea that began in the 2010s continued into the next decade. In 2022, the United States Navy said that China had armed its artificial islands, which are positioned in key areas of the South China Sea, with antiship and antiair missiles and jamming equipment intended to deter and disrupt foreign operations in the sea. By that time, the US estimated that China had militarized at least three islands. The US Navy considered China's military buildup in the South China Sea to be the largest amassing of military assets in the area since World War II. The islands, which were equipped with airfields and other key military infrastructure, operated as staging areas that allow the Chinese military to exert its influence in the South China Sea far beyond what the previous mainland bases allowed.

Other incidents throughout the early 2020s ensured that tensions remained high in the South China Sea. At that time, China claimed sovereignty over 90 percent of the sea's area, a claim that infringed on the exclusive economic zones (EEZs) of Vietnam, Malaysia, Brunei, Indonesia, and the Philippines. The navies of the US and China continued to confront each other periodically, leading to occasional close calls. For example, in October 2023, a Chinese fighter jet allegedly flew within ten feet of a US bomber.

Tensions between China and the Philippines have grown particularly acute since 2023. Repeated confrontations at strategic locations such as the Second Thomas Shoal and Scarborough Shoal have included aggressive maneuvers such as the use of water cannons, dangerous blocking, and even laser pointing. In February 2023, a China Coast Guard vessel aimed a “military-grade” laser at the Philippine patrol ship BRP Malapascua during a resupply mission—an act that the Philippine government formally protested as a deliberate and dangerous provocation. In August of the same year, Chinese vessels engaged in water-cannon harassment and risky maneuvers while attempting to block Philippine resupply boats near Second Thomas Shoal.

Tensions escalated further in June 2024 when the China Coast Guard interfered with another Philippine resupply mission, with reports of boarding, injuries, equipment damage, and confiscation of firearms. The Philippines has responded by steadily strengthened its defense posture. It has markedly deepened security ties with the United States through expanded joint patrols and exercises, including air and maritime drills over the South China Sea in May 2025. At that time, the Philippines and the United States held their first joint maritime drills involving both coast guards, navies, and air forces in the South China Sea, near Palawan and Occidental Mindoro. The exercises, which included communication and search-and-rescue drills, were the second such activity in 2025 and the sixth since joint operations began in 2023. The drills aimed to improve cooperation and strengthen defense ties as tensions with China over territorial disputes continued in the region.

The Philippines has also amplified its military collaboration with other allies, including planned defense agreements with Australia. Philippine Defense Secretary Gilberto Teodoro said the new defense pact would allow more frequent joint military drills to improve cooperation and strengthen regional security.


Bibliography

Flores, Mikhail. "Philippines, Australia to Seal New Defence Pact as China Tensions Rise ." Reuters, 22 Aug. 2025, www.reuters.com/world/china/philippines-australia-seal-new-defence-pact-china-tensions-rise-2025-08-22/. Accessed 22 Aug. 2025.

Friar, Karen. "China’s artificial islands in before-and-after photos." Market Watch, 4 Jan. 2016, www.marketwatch.com/story/chinas-artificial-islands-in-before-and-after-photos-2015-10-27. Accessed 8 Apr. 2022.

Holt, Sean M. "Five Countries, Other Than China, Most Dependent on the South China Sea." CNBC, 17 Nov. 2022, www.cnbc.com/2022/11/18/five-countries-other-than-china-most-dependent-on-the-south-china-sea.html. Accessed 25 Mar. 2024.

Huang, J., and Andrew Billo, eds. Territorial Disputes in the South China Sea: Navigating Rough Waters. Palgrave MacMillan, 2015.

Jung, Ann. "ASEAN and the South China Sea: Deepening Division." The National Bureau of Asian Research, 16 July 2012, www.nbr.org/publication/asean-and-the-south-china-sea-deepening-divisions/. Accessed 8 Apr. 2022.

Manguin, Pierre-Yves. "Trading Ships of the South China Sea." Journal of the Economic and Social History of the Orient, 36.3 (1993): 253-80, search.ebscohost.com/login.aspx?direct=true&db=edsjsr&AN=edsjsr.10.2307.3632633&site=eds-live. Accessed 8 Apr. 2022.

"Philippines Removes South China Sea 'Floating Barrier' Installed by China." Al Jazeera, 25 Sept. 2023, www.aljazeera.com/news/2023/9/25/china-defends-south-china-sea-floating-barrier-as-manila-vows-to-remove. Accessed 25 Mar. 2024.

"Philippines, U.S. Hold Joint Maritime Drills in South China Sea ." Reuters, 20 May 2025, www.reuters.com/world/china/philippines-us-hold-joint-maritime-drills-south-china-sea-2025-05-21/. Accessed 22 Aug. 2025.

Shankar, Sneha. "Taiwan to Build $100M Port in Disputed Region of the South China Sea but China Does Not React." International Business Times, 26 May 2014, www.ibtimes.com/taiwan-build-100m-port-disputed-region-south-china-sea-china-does-not-react-1590010. Accessed 12 Apr. 2022.

Shen, Jianming. "China’s Sovereignty over the South China Sea Islands: A Historical Perspective." Chinese Journal of International Law, vol 1, no. 1, 2002, pp. 94-157, academic.oup.com/chinesejil/article/1/1/94/362104. Accessed 11 Apr. 2022.

Zhen, Liu. "Chinese Naval Group Heads to Disputed South China Sea for Combat Drill." South China Morning Post, 6 May 2016, www.cnbc.com/2016/05/05/chinese-naval-group-heads-to-disputed-south-china-sea-for-combat-drill.html. Accessed 11 Apr. 2022.


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