Published on 06/25/2025
by Captain Elizabeth A. Quinn
Due to its strategic significance and the contention among bordering territories, the South China Sea presents an escalating threat to the United States and its allies. The 1.4-million-square-mile body of water1 serves as a crucial connection between the Western Pacific and the Indian Ocean; it is of significant economic importance for the oil, gas, trade, and fishing industries. China, Vietnam, Taiwan, Malaysia, Brunei, and the Philippines contest this vital waterway. Should China or other Pacific nations resort to forceful measures to assert control over the South China Sea, the United States must be fully prepared to support and defend its allies in the region. Given the complex and varied terrain of the South China Sea area, including maritime and coastal environments, U.S. Army engineers must be adept at amphibious operations. To achieve operational success, the Army must develop tailored engineering doctrine and specialized engineer training focused on amphibious environments.
The unique geographical features and environmental conditions in the area of the South China Sea significantly impact Army operations. Numerous mangroves, shallow reefs, submerged banks, and islands such as the Spratlys and Paracels pose both opportunities and challenges for ground operations.2 For example, the low-lying nature of many of the islands makes building and maintaining military infrastructure, such as airfields, seaports, and other facilities, complex and costly. The shallow waters around these islands complicate the use of amphibious landing craft, which can be difficult to navigate around coral reefs and submerged obstacles, as experienced during various military operations in the region. The rugged terrain on some of the islands can impede the movement of troops and vehicles, making ground and engineer operations more challenging. Additionally, adverse weather events and conditions, such as typhoons and high humidity, cause further complications to operations in this type of environment. The complex terrain and geography in the area of the South China Sea necessitate innovative and adaptive military strategies to ensure successful operations in the area.
Although the U.S. Navy and U.S. Marines may be obvious first choices for conducting amphibious operations, the United States has called upon the Army for such operations multiple times throughout history. In fact, the Army operated in these types of environments from the Revolutionary War to the Spanish-American War.3 From these experiences, the Army created amphibious doctrine and, in 1942, even established the Army Amphibious Training Center, which trained tactical units on embarking troops and equipment onto small boats, approaching and landing on a hostile beach, establishing a beachhead, and preparing and initiating an attack on an island.4 Amphibious operations continued to be pursued following the conception of the Army Amphibious Training Center. For example, Soldiers faced significant obstacles, including extensive minefields, submerged obstacles, and fortified defenses that impeded Allied landings, on Omaha Beach, France, during the 1944 Normandy invasion. Army engineers managed beach obstacles under fire and quickly coordinated solutions for temporary ports.5 Similarly, in the 1991 Gulf War, the rapid establishment of forward operating bases in desert and marshy areas highlighted the need for engineered solutions to handle waterlogged terrain conditions. In addition, Soldiers were required to contend with complex beach and shoreline obstacles while establishing beachheads and supply lines.6 These experiences demonstrate the importance of following specific engineering procedures in an amphibious environment. By developing doctrine that explicitly addresses these types of scenarios, engineers can be well-equipped with the knowledge necessary to construct effective landing zones, manage waterlogged terrain, and maintain mobility in maritime environments.
Amphibious training is essential for Army engineers because it equips them with the specialized knowledge and skills required to effectively operate in environments where land and sea intersect. Amphibious engineer training ensures that engineers are prepared to handle the complex challenges of coastal operations, such as constructing and maintaining infrastructure in unstable, waterlogged conditions or ensuring mobility for beach attacks. Historical examples highlight the importance of such training: During the 1944 Battle of Guam, Army engineers were tasked with establishing vital landing zones and supply routes under harsh conditions, including rugged terrain and unpredictable tides; the success of these operations was directly linked to the engineers’ ability to rapidly adapt their techniques to the amphibious environment.7 Operational environments that include shallow reefs, unpredictable tides, underwater obstacles, and submerged mines require specialized techniques for reconnaissance and clearance. While all Army elements and engineers should have some knowledge of these operational environments, a brigade size element (at least) should be well-trained and adequately equipped to support amphibious operations.
Finally, an amphibious operation is naturally a joint effort. While the Navy and Marines are capable of completing successful amphibious missions, their small units constrain their ability to sustain operations over long periods. Therefore, the Army should conduct joint training with its Navy and Marine counterparts to ensure effectiveness and cohesion during a potential South China Sea conflict.
In conclusion, the strategic significance of the South China Sea and the potential for conflict in the region highlight the critical need for specialized Army engineer doctrine tailored to amphibious operations. Historical examples from past conflicts illustrate the importance of well-defined procedures and training in overcoming challenges in complex maritime and coastal environments. Given the unique complexities of the South China Sea area, including its geography and potential underwater threats, developing and implementing specific amphibious training will ensure operational success and maintain strategic advantage. The United States can enhance its ability to support its allies and effectively respond to threats in the Pacific by preparing Army engineers with the knowledge and skills required to operate in amphibious environments.
Endnotes:
1Rebecca Ratcliffe, “South China Sea: A Visual Guide to the Key Shoals, Reefs, and Islands,” inkl,
<https://www.inkl.com/news/south-china-sea-a-visual-guide-to-the-key-shoals-reefs-and-islands>, accessed on 28 January 2025.
2Ibid.
3Joseph E. Malone, “The Army and the Need for an Amphibious Capability,” School of Advanced Military Studies, Fort Leavenworth, Kansas, January 2015, <https://apps.dtic.mil/sti/tr/pdf/AD1001650.pdf>, accessed on 28 January 2025.
4Marshall Becker, Historical Section Army Ground Forces, Amphibious Training Center Study No. 22, 1946, <https://apps.dtic.mil/sti/tr/pdf/ADA954909.pdf>, accessed on 28 January 2025.
5Alfred M. Beck et al., “The Corps of Engineers: The War on Germany, U.S. Army Center of Military History, 1985, <https://www.history.army.mil/html/books/010/10-22/CMH_Pub_10-22.pdf>, accessed on 28 January 2025.
6Janet A. McDonnell, “Supporting the Troops: The U.S. Army Corps of Engineers in the Persian Gulf War,” U.S. Army Corps of Engineers Library, 1996.
7“Guam—Operations of the 77th Division,” U.S. Army Center of Military History, 1989, <https://www.history.army.mil/html/books/100/100-5/>, accessed on 28 January 2025.
Captain Quinn holds a bachelor’s degree in marine science from the University of Maine, Orono, and is pursuing a graduate degree in geological engineering at the Missouri University of Science and Technology at Rolla.