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Why Indonesia Needs to Expand Its Submarine Fleet

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Why Indonesia Needs to Expand Its Submarine Fleet

Given tight budget constraints, submarines offer Indonesia’s navy the greatest bang for its buck.

Why Indonesia Needs to Expand Its Submarine Fleet

The Pasopati Submarine Museum in Surabaya, Indonesia.

Credit: Depositphotos

2021 was an intriguing year for those with an interest in the development of Indonesia’s defense posture, as the country continued to embark on its journey toward the modernization of its National Armed Forces (TNI). Throughout the year, observers have been discussing, among other things, the Ministry of Defense’s target of procuring big-ticket items, including major surface combatants, submarines, fighters, multirole tanker transports, as part of its ambitious $125 billion long-term modernization plan.

With the effort undoubtedly set to continue this year, it is an opportune time to revisit one of the perennial debates about Jakarta’s military build-up: namely, should Indonesia possess the capability to project power and engage potential adversaries outside its territory? A look at the TNI’s current and future operational demands could provide an answer to this question.

Technological advancements and the proliferation of long-range precision-guided munitions (PGMs) have made it possible for capable adversaries to strike Indonesia’s critical infrastructure without even entering the country’s 200-nautical-mile Exclusive Economic Zone (EEZ). One could argue that this does not necessarily mean that TNI – particularly the navy (TNI-AL), which has the primary responsibility for power projection in an archipelagic country like Indonesia – must venture out and find a potential enemy. Arguably, it could opt to stay put and shoot down enemy PGMs without incurring the risk by operating beyond Indonesia’s maritime territory.

However, this “war from home” strategy will drag the military into a more complex and expensive salvo war aimed at intercepting all of the enemy’s PGMs instead of proactively finding and destroying the launchers (ships, aircraft, airbases, etc.), sensors, and weapon guidance systems that are dispatching them. Even for a country that has an advanced global missile defense system like the United States, this completely passive approach is not recommended, as evidenced by Washington’s continued work to develop its “Left of Launch” strategy to offensively destroy enemy missiles before they are launched. After all, it is more efficient to “kill an enemy’s archers instead of its arrows.”

Such a view, which ignores the need for a modern military to operate outside its national territory in the event of a high-intensity conflict, also undermines the country’s national defense doctrines as a whole. In many recent strategic documents released by the Ministry of Defense, it is clearly stipulated that Indonesia employs a multilayered defense system that incorporates what is referred to as a mandala pertahanan luar or “external defense theatre” outside its EEZ. More specifically, TNI’s joint doctrine, the Tri Dharma Eka Karma (or Tridek for short), envisions the armed forces being able to destroy the enemy at its base, en route, or upon entry into the country’s territory. Moreover, the navy’s Archipelagic Sea Defense Strategy highlights the importance of having the strategic and operational reach to conduct operations in areas beyond Indonesia’s national borders with little or no warning.

In essence, Jakarta should ideally develop a military that can operate far beyond its territorial waters in order to engage with an enemy, or at least detect enemy activity. In consequence, a naval posture that can support such long-range missions, or to borrow a more popular term, a navy with substantial “blue water” capability, is needed with operating ocean-going platforms as one of the key enablers. Unfortunately, due to Indonesia’s underlying budget constraints, the government does not have the luxury of procuring all of the naval-related platforms necessary to fulfill this goal. The government must therefore prioritize, and we believe the most effective long-term investment is to expand the country’s submarine fleet. Here is why.

First, due to their inherent stealthiness, submarines can provide greater strategic deterrence than most, if not all, other naval assets, which are considerably more detectable, particularly in contested areas. Hence, it is a perfect platform to meet the aforementioned  operational demands of TNI regarding long-range intelligence, surveillance, and reconnaissance operations, and, more importantly in the current security context, strike capability.

To fully optimize all these advantages, Indonesia should try to get its hand on bigger and more advanced submarines that offer greater time on station and greater breakthrough capability than those that make up its current fleet. Submarines must be able to be deployed for at least 60 consecutive days in order to accomplish the aforementioned missions. This type of submarine must also incorporate key technologies that are still politically and financially viable, such as lithium-ion battery, Very Low Frequency (VLF) communications systems and/or submarine-launched anti-ship missiles. Acquiring these new types of submarines would bolster the Indonesian submarine fleet’s underwater endurance, survivability, and firepower.

Second, TNI-AL has pride in being one of the oldest and most experienced submarine operators in the region, having operated submarines since 1959. For more than six decades, the “silent service” has been central in ensuring deterrence throughout the country’s vast waterways, and military and political leaders cherish its strategic weight. The service has even attested to its value against foreign naval forces, particularly during the India-Pakistan War of 1965 when Jakarta dispatched two of its Whiskey-class submarines to Karachi, and in 1999 when one of its Type-209 submarines successfully shadowed the fleet of the International Force East Timor. This long operational history means that the navy has cultivated decades of experience, traditions, and tactics on how to maintain and utilize submarine forces in support of the country’s national interests.

Third, submarine procurement is critical in maintaining the current momentum in the development of Indonesia’s domestic shipbuilding industry. For years, indigenous submarine production and maintenance, repair, and overhaul (MRO) capability has been included as one of the country’s seven defense industry priority programs. The progress has already been demonstrated by the ability of the state-owned shipbuilding company, PT PAL, domestically to assemble KRI Aluguro, the third improved Chang Bogo-class [submarine that Jakarta has ordered from Seoul, and to overhaul the German-made Type-209 submarine KRI Cakra.

In addition, the government has also allocated $194.7 million to the PT PAL shipyard to expand its submarine production capability. Therefore, considering the Indonesian defense industry law that requires foreign suppliers to provide countertrade, local content, and offsets, in order to promote skills and technology transfers, a future submarine acquisition program would keep the submarine powerhouse dream alive and in return support these boats across their full life-cycle.

In conclusion, the reality of modern warfare and the mission requirements listed in Indonesia’s military doctrines clearly demand that TNI develop a decent power projection capability. Of course, ocean-going submarines are not a silver bullet because, like any weapon system, they have inherent strengths and weaknesses. Still, with the credible deterrence that such a fleet would provide, TNI-AL’s mature expertise, and growing production and MRO support from domestic shipyards, submarines with long endurance capability are arguably the prominent strategic asset with the best cost-benefit balance for Indonesia.