Indonesia’s New Military Bases In The South China Sea: Preparing For Friction – Analysis
In February 2024, Indonesia elected Prabowo Subianto as its next president. While he does not take office until October, speculation over whether and how Indonesia’s foreign policy might change is already swirling. Certainly, there have been indications that Prabowo may chart a course that is less in line with the West than that of his predecessor, Joko “Jokowi” Widodo. Indeed, the People’s Republic of China was Prabowo’s first overseas destination after his electoral victory. But even before his election, there had been other indications, such as his off-the-cuff proposal for a peace plan for the Russian-Ukrainian War that would have left most of occupied Ukraine in Russian hands and his particularly harsh criticism of the European Union over its ban on Indonesian palm oil. Both cases stood in contrast to his warm embrace of China and its investments in Indonesia’s strategic nickel mining industry.
However, Prabowo is unlikely to change the current trajectory of Indonesian policy in the South China Sea—the southern portion of which China and Indonesia dispute. Over the last six years or so, Indonesia has responded to the growing number of Chinese incursions into its exclusive economic zone by gradually strengthening its security posture in the region. That strengthening can be best seen in the slow but steady establishment and expansion of military bases on the Natuna Islands (or the Riau Islands in Indonesia), just south of the disputed waters. That development is likely to continue under Prabowo, who served as Jokowi’s minister of defense for the last five years. Once finished, the bases will enable Indonesia to better monitor and respond to any foreign incursions into its exclusive economic zone.
Less Neutral, More Wary
Building bases, of course, is not the traditional tack that Jakarta has taken. Rather, it has long played down its maritime dispute with China in the South China Sea, particularly in public. Indonesia’s former foreign minister, Marty Natalegawa, epitomized that approach in his oft-repeated assertion that “between Indonesia and China, there is no territorial dispute.” Narrowly speaking, that is true. But China’s “nine-dash line” claim in the South China Sea does overlap a substantial swath of Indonesia’s exclusive economic zone near the Natuna Islands, where some of the country’s richest fisheries and largest offshore natural gas fields lie.
What resistance Jakarta did mount against Beijing’s “nine-dash line” claim was restrained in the past. When Indonesia’s United Nations mission rebutted Beijing’s claim in 2010, it did so obliquely by citing China’s own recognition of other countries’ (presumably also Indonesia’s) exclusive economic zone rights under the United Nations Law of the Sea Treaty. Also softening its rebuttal’s blow, Indonesia reiterated its willingness, as a “neutral party,” to help establish confidence-building measures among the South China Sea’s claimants and referenced its part in the Association of Southeast Asian Nations’ perennial negotiations over a South China Sea code of conduct.
Far from taking the hint, China facilitated more incursions into Indonesia’s exclusive economic zone. It subsidized the fuel that Chinese fishing boats needed to make the long journey to the region and sent Chinese coast guard ships to accompany them. Chinese naval vessels soon followed. Then, in 2014, as if to solidify its claim to the disputed waters, Beijing unveiled a new official map that showed them as an integral part of continental China. Indonesian defense officials bristled.
General Moeldoko, then chief of the Indonesian armed forces, traveled to Beijing and privately impressed upon his Chinese counterparts that Indonesia would protect its claims in the region. He then went a step further. He published a lengthy op-ed in the Wall Street Journal in which he publicly expressed Indonesia’s dismay with China over the map and noted that, as a result, “the Indonesian military has decided to strengthen its forces on Natuna.” Unfortunately for Moeldoko, constraints on Indonesia’s defense budget at the time prevented him from quickly boosting the military’s permanent presence on the Natuna Islands—a step that would have given his statement greater weight. So, although Jakarta announced plans to improve Indonesia’s defense posture in the region, it made meager progress on them.
Instead, Jakarta tried to demonstrate its resolve with occasional shows of force. It began to seize foreign fishing boats in its exclusive economic zone and blow them up, including a few Chinese ones. But doing so did not temper China’s behavior. In March 2016, a Chinese coast guard vessel rammed a Chinese trawler that Indonesian authorities had stopped to prevent it from being taken in tow. Three months later, several Chinese coast guard vessels aggressively maneuvered to coerce an Indonesian navy corvette into releasing a Chinese trawler that it had captured. Another three months on, a Chinese coast guard vesselengaged in a three-day standoff with an Indonesian patrol boat within Indonesia’s exclusive economic zone. In response, Jakarta ordered most of its air force’s operational Su-30 and F-16 fighter jets to conduct a major military exercise over the Natuna Islands.
Growing the Bases
The incidents in 2016 seemed to mark a turning point for Indonesia. Though the military’s 2008 strategic review had envisioned new military bases and joint combat units on the Natuna Islands, funding to create them had been lacking. Following what appeared to be increased Chinese assertiveness not only near the Natuna Islands, but also across the South China Sea, Indonesia’s legislature began to allot the funds necessary for “major upgrades to military facilities in the Natuna Islands.” Taking a further jab at China’s maritime claims, Indonesia’s Coordinating Ministry of Maritime Affairs leaked a new map that renamed the waters around the Natuna Islands as the North Natuna Sea.
By 2018, the product of Indonesia’s new funding began to take shape with its establishment of a new military presence on Great Natuna Island (or Pulau Natuna Besar in Indonesian), the largest island in the Natuna archipelago. That presence initially consisted of two Raider infantry companies. They formed the core of Composite Battalion 1, a new joint combat unit based at
Sepempang. At the time of the unit’s activation, Air Chief Marshal Hadi Tjahjanto, the chief of the Indonesian armed forces, hailed it as “part of our strategic plans . . . to provide deterrence against threats, especially at the borders.”
Two years later, the Indonesian military augmented the battalion with new units. Rounding out its ground combat elements were a marine composite company and an army combat engineer company, both based at South Cemaga. Soon after, the army attached a battery of Astros II self-propelled multiple launch rocket systems to extend their defensive reach out to sea. Posted to Teluk Buton, at the northern tip of Great Natuna Island, the battery can strike targets as far as forty kilometers away with guided rockets and as far as three hundred kilometers if armed with AV-TM 300 anti-ship missiles. And to protect the battalion from air attack, the army assigned an air defense battery equipped with short-range StarStreak missiles for point defense against cruise missiles and strike aircraft.
Jakarta has also laid plans to lengthen and widen the runway of Raden Sadjad Air Base on Great Natuna Island. Doing so would allow two fighter jets to take off and land at the same time, thereby enabling the base to support larger and higher-tempo operations. Already, the Indonesian air force has built two aircraft hangars at the base and permanently stationed Air Squadron 52 there. The squadron fields several CH-4 unmanned aerial vehicles (UAV), which can not only conduct area surveillance, but also perform target acquisition for the army’s Astros II battery. A detachment of four AH-64 attack helicopters , likely armed with AGM-114 missiles, is also expected to be stationed at the base in time. And finally, the air force has allocated three special forces (Paskhas) detachments to defend the base. One of them is equipped with Skyshield 35air defense systems for short-range air defense against low-flying aircraft and unmanned systems.
The Indonesian navy has also raised its profile around the Natuna Islands. Since 2020, it has maintained a consistent presence of at least three frigates and corvettes there. It also began construction on a submarine support base in the Lampa Strait, possibly near Sabang Mawang Naval Station on Lagong Island. Such a base would improve the navy’s ability to conduct longer and more frequent submarine patrols in the South China Sea. Recently, the navy established the 1st Fleet Naval Combat Group at Ranai to better orchestrate the support services needed for not only its warships based in the area, but also those it could deploy there. Lending additional support for those operations, the navy commissioned a new naval base near Pontianak in West Kalimantan and acquired land for a naval aviation base on Jemaja Island, according to Jane’s World Navies in 2023.
Both the Indonesian air force and navy have pursued similar base-building strategies. Both sought to add capacity that would enable them to sustain larger and longer-term deployments around the Natuna Islands. As if to reinforce their need to do so, sixty Chinese fishing boats, escorted by Chinese coast guard vessels, sailed into Indonesia’s exclusive economic zone near the islands in 2020. Over two weeks, Indonesia dispatched a large force of four F-16 fighters, four frigates, two corvettes, a submarine, and a landing platform dock with six hundred marines to the area. Recognizing that China used similar large-scale incursions to assert its sovereignty and undermine Philippine maritime claims in the South China Sea, the Indonesian military is clearly preparing itself to counter such challenges in the future.
Indeed, Indonesia’s new base facilities and forces have already come in handy. In 2021, Chinese survey ships and coast guard vessels entered an offshore natural gas exploration area known as the Tuna block, which Indonesia administers. As a result, it quickly deployed air and naval patrols from bases on Great Natuna Island to confront them. Both sides shadowed each other for months. Then, in 2023, when Jakarta approved the drilling of an exploration well there, the Chinese coast guard sent its largest vessel to the area. Again, Indonesia dispatched a warship, a maritime patrol aircraft, and a CH-4 UAV from its Natuna bases to monitor it.
Prabowo’s Path
During Jokowi’s tenure, Indonesia has clearly improved its ability to oversee its “archipelagic sea lanes,” what Indonesian strategists call the waterways that connect their country’s 17,500 islands and link them to the rest of the world. Indonesia’s new military bases on and near the Natuna Islands are physical manifestations of that progress. They and the forces stationed at them make it easier for Jakarta to monitor and respond to foreign incursions into its exclusive economic zone, especially in the South China Sea. Along with Indonesia’s concurrent military modernization, they signal the country’s continued interest in strengthening its maritime security.
As a former general and later as Jokowi’s minister of defense, Prabowo has long been involved in these efforts. Over the past two decades, he has seen China’s maritime presence in the South China Sea steadily expand—most recently at a Cambodian naval base. No doubt, Prabowo is concerned, as are many of his former military colleagues. That is unlikely to change, given China’s aggressiveness towards other South China Sea claimants, as evidenced by the Chinese coast guard’s clash with Philippine supply boats near Second Thomas Shoal in June 2024.
Eventually, Indonesia’s base building and military deployments on and near the Natuna Islands could generate a momentum of their own. They enable stepped-up Indonesian patrols which are likely to encounter Chinese maritime forces with greater frequency. That, in turn, could result in incidents that require Prabowo to choose between Indonesia’s maritime interests and its economic relations with China. Time will tell what he will do. But it seems probable that Prabowo will prioritize the former over the latter.