China's Island Fortresses are a Disaster Waiting to Happen

A third of global sea shipments pass through the South China Sea, creating a crucial geopolitical region. China has constructed artificial islands on the Spratly Islands, a collection of tiny reefs and rocks, despite overlapping claims from several countries. These islands, dubbed the 'Great Wall of Sand' by Admiral Harry Harris, involved massive dredging operations, creating 3,200 acres of new land. These new landmasses now host military bases equipped with runways for heavy bombers, deep-water harbors, radar arrays, missile shelters, and hardened aircraft hangers.

China's primary motivation for building these islands stems from its 'Malacca dilemma,' where crucial shipping routes, especially for oil, pass through narrow choke points controlled by other nations. By controlling the South China Sea, China gains strategic options and reduces vulnerability. China claims most of the South China Sea based on 'historic rights,' citing fishermen and traders using the waters for centuries. This claim is challenged by Vietnam, the Philippines, Malaysia, Brunei, and Taiwan, and largely unsupported under international law (UNCLOS). The area also holds significant resources, including an estimated 11 billion barrels of oil, 190 trillion cubic feet of natural gas, and rich fishing grounds. China's island building began escalating in the 1990s, notably on Mischief Reef and Scarborough Shoal. The strategic logic was to extend radar coverage, push missile umbrellas further from the mainland, and create anti-access/area denial zones, making it costly for adversaries to operate in the region.

Building these islands required a starting point (coral reefs), vast amounts of sand, and a sophisticated industrial fleet. China used some of the largest cutter suction dredges, like the Tanjingha, which act as enormous vacuum cleaners, to pump sand and crushed coral onto submerged reefs 24 hours a day. From December 2013 to October 2015, approximately 3,200 acres of new land were created across seven reefs. Once built, these islands were fortified with concrete foundations, rock armor, and seawalls. Fiery Cross Reef, for example, features a 3 km runway, a large harbor for naval vessels, and point defense positions with anti-aircraft guns and short-range missiles. Subie Reef and Mystery Reef follow a similar blueprint. Underground storage facilities for ammunition and fuel, as well as shelters for mobile missile launchers, suggest long-term investment. This construction buried approximately 13 square kilometers of coral reef ecosystems, and dredging further damaged a wider area. Chinese fishing fleets also damaged over 100 square kilometers of coral habitat through unsustainable practices. In 2016, an international tribunal at The Hague ruled that China's land reclamation caused severe harm to coral reefs and violated international law, a ruling Beijing rejected.

The artificial islands, despite their impressive construction, are fundamentally fragile. Unlike aircraft carriers, they are immobile targets, known to adversaries, and within range of various advanced weapons from the US and regional powers. They sit inside overlapping weapons envelopes, making them vulnerable to saturation attacks that could cripple runways and radar systems early in a conflict. Logistically, these bases depend on supply lines stretching hundreds of kilometers across open water, making them expensive to maintain in peacetime and highly vulnerable to interdiction by submarines, surface ships, mines, or blockades in wartime. Additionally, intense tropical weather, including typhoons, salt corrosion, humidity, and heat, impose significant maintenance burdens, and the dredged sand and coral foundations are prone to subsidence and erosion.

In 2013, the Philippines took China to the Permanent Court of Arbitration in The Hague regarding its claims. The tribunal ruled in 2016 that China had no legal basis for historic rights within the nine-dash line and that its artificial islands built on low-tide elevations do not generate territorial seas. It also found China guilty of environmental damage. While China rejected the ruling, it provided a legal framework for other claimants and supported freedom of navigation operations by the US and its allies. The ruling also spurred new defense arrangements like AUKUS. Ironically, other countries like Vietnam, Taiwan, Malaysia, and the Philippines have started expanding their own artificial islands in response. This has led to increased tensions and confrontations, such as collisions and water cannon incidents between Chinese and Philippine vessels. These fixed, high-value military assets create 'crisis instability,' pressuring both sides to act early in a conflict to avoid losing valuable assets or triggering a larger war. Furthermore, the islands pose a significant humanitarian and environmental risk; a conflict could lead to environmental disaster due to strikes on fuel depots and ammunition bunkers, and the thousands of personnel stationed on these isolated outposts would face limited evacuation options.