USS Abraham Lincoln Drills Show Naval Readiness and Environmental Strain in South China Sea

January Gunfire in a Crowded and Contested Sea

On January 8, 2026, the USS Abraham Lincoln fired its Phalanx Close-In Weapon System above the South China Sea, sending radar guided rounds skyward from the flight deck. Photographs released by the Defense Visual Information Distribution Service captured the live fire exercise aboard the Nimitz-class aircraft carrier, which operates on nuclear power.

About 3,200 sailors and nearly 90 aircraft were aboard as the carrier conducted training in waters that carry roughly 30 to 40 percent of global shipping traffic by certain measures. Smartphones, automobile parts and fuel move through this maritime corridor, making security there a concern far beyond the countries along its shores.

The same sea contains approximately 571 species of corals that build reefs, a concentration comparable to the Coral Triangle. Thousands of other marine species, including reef fish and sea turtles, depend on its waters. Military readiness, commercial shipping and the survival of vulnerable habitats meet in the same crowded space.

The January exercise was part of a deployment that soon changed direction. By January 15, the Abraham Lincoln and its escorts were heading west toward the Middle East amid growing tensions with Iran. The carrier arrived in the Arabian Sea on January 26, adding roughly 5,700 service members to the region's military presence.

Its departure ended three months of continuous American carrier presence in the South China Sea. Yet joint patrols with the Philippines continued, showing how Washington maintained operations through smaller ships, aircraft and partnerships while its carrier moved to another theater.

What the Carrier Was Practising

The Abraham Lincoln departed San Diego on November 24, 2025, accompanied by the guided missile destroyers USS Spruance, USS Michael Murphy and USS Frank E. Petersen Jr. The carrier had been operating in the South China Sea since December 26.

The strike group carried out flight operations, replenishments at sea, damage control training and explosive ordnance disposal drills. Together, these activities prepare a naval force to launch aircraft, receive supplies without returning to port, respond to emergencies and handle explosive threats.

On January 8, sailors from Explosive Ordnance Disposal Mobile Unit 1 practised descending by rope from an MH-60S Sea Hawk helicopter onto the carrier's deck. Embarked F/A-18E/F Super Hornet fighters also took off during air wing exercises, demonstrating the carrier's ability to project military power across a heavily travelled maritime region.

Commander Matthew Comer, a spokesman for the U.S. 7th Fleet, described the activities as "routine operations" intended to deter aggression, strengthen alliances and advance peace through strength.

Captain Dan Keeler, the Abraham Lincoln's commanding officer, linked the deployment to both military capability and regional relationships when the carrier arrived in Guam in mid-December.

My crew is excited to be back in this area of the world, and we look forward to demonstrating what an aircraft carrier and carrier strike group bring to the fight. Our sailors are eager to learn from new cultures and strengthen partnerships across the region throughout our deployment.

Taiwan Exercises Added to Regional Tensions

China conducted live fire exercises around Taiwan on December 29 and 30, 2025, shortly after the Abraham Lincoln began operating in the South China Sea. The drills, named "Justice Mission 2025," encircled the island, which lies strategically between the East and South China seas.

China's Eastern Theater Command described the exercises as a "punitive and deterrent action" against Taiwan and countries supporting its independence. Beijing regards the democracy, which governs itself, as a breakaway province that must be reunited with the mainland, using force if necessary.

American and Chinese military demonstrations therefore unfolded close together in time, against an already tense regional backdrop. President Donald Trump said during this period that Taiwan's fate was "up to" Xi Jinping, while also warning that he would be "very unhappy" about a Chinese attempt to seize the island by force.

Trump explained his position on Xi's view of Taiwan and the possibility of military action:

He considers it to be a part of China, and that's up to him what he's going to be doing. But I've expressed to him that I would be very unhappy if he did that, and I don't think he'll do that. I hope he doesn't do that.

The Trump administration had announced $11.1 billion in arms sales to Taiwan the previous month, described as the largest weapons package ever for the island. The sales placed material support for Taiwan alongside presidential language that left room for uncertainty about Washington's response to a crisis.

The 1979 Taiwan Relations Act governs American interactions with Taiwan. It requires the United States to ensure that Taiwan receives resources needed to defend itself, without strictly requiring American military intervention if China invades. This approach is commonly called strategic ambiguity: Taiwan receives support, while the exact American response to an attack is left uncertain. Regular carrier deployments form another part of that posture.

A Deployment That Changed Direction Quickly

The Abraham Lincoln's movements connected events in the Pacific with a growing military buildup near Iran. The sequence also shows how briefly its South China Sea operations lasted before new orders redirected the strike group.

• November 24, 2025: The Abraham Lincoln departed San Diego with three guided missile destroyers.
• Mid-December 2025: The carrier arrived in Guam, where Captain Dan Keeler discussed readiness and regional partnerships.
• December 26, 2025: The carrier began operating in the South China Sea.
• December 29 and 30, 2025: China conducted its Justice Mission 2025 exercises around Taiwan.
• January 8, 2026: The Abraham Lincoln conducted its Phalanx firing exercise and helicopter rope training.
• By January 15, 2026: The strike group was moving west toward the Middle East.
• January 26, 2026: The carrier arrived in the Arabian Sea.
• January 28, 2026: American and Philippine vessels conducted joint operations near Scarborough Shoal.

The carrier's departure came only days after the January 8 training. Its reassignment moved a major concentration of aircraft, ships and personnel from one area of tension to another, while American forces remaining in the Pacific continued their operations.

Reefs Already Face Extensive Damage

Satellite and field analyses have documented at least 8,000 acres of damaged reef across the South China Sea. Approximately two thirds of that destruction was linked to extensive dredging and artificial island construction, primarily by China.

Dredging removes or moves material from the seabed. When carried out around reefs, it can change the physical structure on which marine life depends. Scientists warn that dredging and island construction can cause lasting, sometimes irreparable damage to habitats that support food security and help protect coastal communities from storms.

The environmental pressure extends beyond places where construction has occurred. Fisheries in the South China Sea support millions of livelihoods and supply a primary source of protein for regional populations. Damage to habitats can therefore affect both wildlife and the communities that depend on the sea for food and income.

Military activity adds another source of pressure to waters already used intensively by commercial vessels. Live fire exercises introduce powerful bursts of energy into the air and water, while fragments and acoustic disturbances can enter the marine environment even when weapons are aimed away from other ships.

Research on naval exercises in other ocean basins indicates that explosives and intense sound can injure fish, harm invertebrates and disrupt feeding or spawning. Shipping traffic and seismic surveys also contribute to underwater noise, making military exercises part of a wider environmental burden.

Noise Risks and the Limits of Deployment Data

Studies have linked intense sonar and similar acoustic sources to mass strandings of beaked whales and other cetaceans. Recorded effects range from changes in behaviour to physical injury. Whales and dolphins are among the marine mammals addressed in American assessments of naval training.

No published study has isolated the environmental footprint of this particular Abraham Lincoln deployment. Measuring it would be difficult in a complex ecosystem exposed to shipping, construction, fishing and other military activity at the same time.

Marine experts caution that repeated exercises add noise, pollution and physical risks to a sea that is partly enclosed and whose biological systems are already close to their tolerance limits. For coastal communities, the concern is the accumulated burden on waters that provide food, work and natural protection.

The U.S. Navy has acknowledged environmental responsibilities through detailed environmental impact statements for its training ranges. NOAA Fisheries authorizations describe acoustic and explosive stressors as likely to affect whales, dolphins and other marine mammals.

Required protective measures include exclusion zones and rules requiring activities to stop when animals are spotted in operational areas. These measures connect the practical conduct of training, including where and when an exercise proceeds, with efforts to reduce harm to marine life.

Maritime Law and Scarborough Shoal

The 1982 United Nations Convention on the Law of the Sea provides the main legal framework for these waters. The United States has not ratified the treaty, although it generally observes its provisions on innocent passage and exclusive economic zones. Those provisions help govern how ships move through coastal waters and how coastal states exercise rights over nearby resources.

In 2016, an arbitral tribunal under the Permanent Court of Arbitration ruled that sweeping historic claims to the South China Sea had no legal basis under the convention. The proceedings also found that extensive land reclamation had severely harmed coral reefs and violated obligations to protect fragile ecosystems and the habitats of threatened species.

Environmental responsibilities extend across the region's operating states. The United States and coastal countries, including the Philippines, Vietnam and Malaysia, face the task of exercising navigation rights while preventing unnecessary damage to marine environments.

The Abraham Lincoln's presence near Scarborough Shoal carried particular sensitivity. The shoal, called Bajo De Masinloc by Manila and Huangyan Dao by Beijing, lies 120 nautical miles off Luzon and has become a focus of renewed friction between China and the Philippines.

In September 2025, China announced plans to establish a national nature reserve there. The announcement fuelled concern about possible land reclamation resembling China's earlier construction in the Spratly Islands. Philippine military leaders vowed to prevent China from establishing a permanent presence at the shoal.

American naval power consequently served two roles in the area: a military deterrent amid territorial tensions and another source of environmental pressure in sensitive waters. The shoal brought those security and conservation concerns together in a single flashpoint.

Iran Tensions Drew the Carrier West

The Abraham Lincoln's redeployment followed growing tensions with Iran and Trump's signals that he was prepared to order strikes if necessary. The president described the naval movement while expressing hope that military action could be avoided.

we have a lot of very big, very powerful ships sailing to Iran right now, and it would be great if we didn't have to use them.

The carrier reached the Arabian Sea on January 26, adding roughly 5,700 service members to the regional force posture. Its strike group joined three other Navy destroyers already in the Middle East theater, two near the Strait of Hormuz and one in the Red Sea, along with three littoral combat ships in the Arabian Gulf.

F-15E Strike Eagle fighter jets also deployed to strengthen combat readiness and regional security. The UK Ministry of Defence contributed Typhoon fighter jets to the defensive posture. The buildup echoed earlier deployments of air defense equipment, including Patriot missile systems, ahead of possible Iranian retaliation.

Some analysts viewed the Lincoln's rapid movement, including its positioning 1,400 kilometers south of Iran's waters, as a recalibration of American priorities. Pentagon officials maintained that the reassignment was a necessary response to emerging threats, rather than a retreat from commitments in the Pacific.

The departure left the South China Sea without an American carrier for the first time in three months. That continuous presence had included the USS Nimitz and USS George Washington strike groups before the Abraham Lincoln arrived.

The Nimitz, which the Abraham Lincoln replaced, returned home ahead of its expected decommissioning later in 2026, after more than 50 years of service. The transition highlighted the competing demands placed on a limited number of carriers as military requirements shifted between regions.

Joint Patrols Continued Without a Carrier

On January 28, the guided missile destroyer USS John Finn joined the Philippine Navy frigate BRP Antonio Luna and Philippine Coast Guard cutter BRP Gabriela Silang for joint patrols near Scarborough Shoal. The operation was the first joint South China Sea activity between Washington and Manila in 2026.

Fighters, surveillance aircraft and helicopters took part alongside the surface vessels in warfare exercises and night operations. The Armed Forces of the Philippines said the activity reflected a shared commitment to maritime security, the ability of forces to work together and an international order based on rules in the Indo-Pacific.

A Chinese Type 054A-class frigate sailed near the formation during the exercises. The People's Liberation Army Southern Theater Command announced its own naval patrols in response and accused Manila of bringing foreign powers into the dispute.

The command said the Philippines had drawn in those powers for "disrupting peace and stability in the South China Sea." The competing operations showed that the carrier's departure had left the underlying confrontation active.

American monitoring also continued through contracted intelligence support, a Marine Corps Reaper drone unit based forward in the region and persistent P-8 Poseidon surveillance flights. These assets provide continuing observation and the ability to respond quickly even when a supercarrier is assigned elsewhere.

The three months of carrier presence off Western Luzon had offered reassurance as the Philippines confronted Chinese activity at Scarborough Shoal. After the Abraham Lincoln left, distributed maritime operations spread the work across ships, aircraft and partners, reflecting the challenge of maintaining influence over vast distances with finite resources.

The Bottom Line

• The USS Abraham Lincoln conducted Phalanx live fire training in the South China Sea on January 8, 2026, alongside air wing and helicopter rope exercises.
• The carrier had operated there since December 26, following its November 24 departure from San Diego with three guided missile destroyers.
• China's December 29 and 30 exercises around Taiwan added to regional tensions, while Washington's $11.1 billion arms package supported Taiwan's defenses.
• At least 8,000 acres of reef damage have been documented in the South China Sea, with roughly two thirds linked to dredging and artificial island construction, primarily by China.
• No published study has isolated this deployment's environmental footprint. Research elsewhere identifies risks from naval noise and explosives to marine life.
• The carrier arrived in the Arabian Sea on January 26 amid tensions with Iran, ending three months of continuous American carrier presence in the South China Sea.
• American and Philippine forces continued joint operations near Scarborough Shoal on January 28, supported by continuing regional surveillance.