The Philippines stands at the center of one of the world’s most contested maritime regions, yet it remains the only frontline state in the South China Sea without a single submarine. This absence is not a minor gap, it is a defining weakness in a moment when the country faces unprecedented pressure from an increasingly assertive China. Every year, Chinese Coast Guard ships, militia vessels, and naval fleet elements push deeper into waters claimed by Manila, saturating areas like Ayungin Shoal, Scarborough Shoal, and Iroquois Reef with a level of presence no other Southeast Asian nation endures. These encounters are not abstract geopolitical events; they unfold daily, shaping the reality for Philippine sailors, fishermen, and military planners who operate under the shadow of a force far larger and more technologically advanced. In this environment, the Armed Forces of the Philippines’ decision to allocate up to US$2 billion for its first submarine fleet is not a matter of prestige or military symbolism. It is a strategic necessity born from geography, vulnerability, and the need for credible deterrence. Among all the countries surrounding the South China Sea, none are as exposed as the Philippines, an archipelago stretched across vital sea lanes, with wide-open maritime borders and an adversary that operates with confidence just beyond its shores. This combination of pressure and vulnerability makes the acquisition of submarines not an option, but an urgent requirement if the country hopes to shift the balance and protect its waters with a deterrent force capable of operating where surface ships cannot.
Strategic Rationale – Why Submarines are Crucial Now
The strategic logic behind the Philippines’ push for submarines begins with geography, a geography that creates both tremendous opportunity and undeniable vulnerability. As an archipelago of 7,641 islands situated along some of the world’s busiest sea lanes, the country sits across maritime routes essential to global trade, military mobility, and regional stability. These waters are not shallow coastal zones but deep, submarine-friendly environments shaped by the Sulu Sea basin, the Philippine Sea, and some of the deepest trench systems on Earth. These natural formations provide an undersea landscape ideal for stealth operations. Surface ships operated by the Philippines can be encircled, chased, or harassed by larger and more numerous Chinese vessels, but a submarine operating beneath the thermocline disappears into an environment where detection becomes extremely difficult, even for advanced navies. That natural advantage is one of the few areas where the Philippines can level the field. It creates a domain where the power imbalance above the surface no longer dictates the outcome below it.
This need for an asymmetric advantage has grown even more urgent as China’s behavior crosses thresholds that were rarely breached in earlier years. What once began as distant shadowing has evolved into a pattern of direct, aggressive encounters. Water-cannon strikes strong enough to injure sailors and shatter equipment, deliberate ramming of vessels, laser targeting against Philippine Coast Guard crews, and the steady increase of communication jamming signal a shift toward coercive, high-pressure tactics. These are not isolated episodes but parts of a coordinated strategy: a three-layered system composed of the People’s Liberation Army Navy, the China Coast Guard, and the maritime militia. Together, they form a continuous presence designed to exhaust, intimidate, and eventually wear down Philippine resolve at strategic points such as Ayungin Shoal, Scarborough Shoal, and Iroquois Reef. In this environment, a Philippine submarine force introduces a weapon China cannot easily corner, block, or overwhelm. A submarine does not need permission to maneuver. It does not broadcast its presence. It cannot be forced aside with water cannons or surrounded by militia boats. It moves in a realm where harassment is impossible because its position is unknown.
This shift toward undersea capability also reflects a broader transformation in the Philippines’ defense priorities. For decades, the Armed Forces of the Philippines focused largely on internal security, counterinsurgency operations, disaster response, and homeland-based missions. The navy, as a result, received limited funding, leaving the country without many of the basic tools required for maritime deterrence. But the security environment has changed, and so has the strategic mindset. Under Re-Horizon 3 of the AFP modernization program, the country has moved decisively toward building a credible external defense posture. Anti-ship missile batteries like BrahMos, new offshore patrol vessels, incoming fighter aircraft, and expanded long-range surveillance capabilities all signal a dramatic recalibration. Submarines represent the apex of this shift, providing a deterrent effect that no other platform can match. Their mere existence forces adversaries to assume risk, reconsider aggressive actions, and plan around uncertainties. It is a capability China cannot ignore, and one that instantly elevates the strategic weight of the Philippines in the regional balance.
These factors make the case clear: submarines are not luxury assets or symbolic purchases. They are the logical answer to the geographic realities, the rising intensity of Chinese pressure, and the fundamental transition in the Philippines’ approach to national defense. No other country in Southeast Asia faces the same combination of exposure, threat, and strategic importance and no other country stands to gain as much from the quiet power of an undersea fleet.
What Submarines Provide That Nothing Else Can?
One of the most compelling reasons the Philippines needs submarines lies in the reality that no conventional surface fleet it can build will ever match China’s sheer naval size. China now operates the world’s largest navy by hull count, with destroyers, frigates, amphibious ships, and a rapidly expanding Coast Guard that can swarm and overwhelm any surface vessel Manila deploys. In that environment, competing ship-for-ship is impossible. But submarines change the equation entirely. They offer something no surface platform can provide: true asymmetric power. A single submarine, even a modest diesel-electric vessel, can threaten high-value Chinese assets, destroyers, landing ships, even carrier support elements, without needing numerical superiority. It can slip into contested waters undetected, wait quietly in depth, and force a far larger navy to devote extraordinary resources to anti-submarine operations. This is not theoretical. Vietnam’s Kilo-class submarines have already shaped Beijing’s calculus in the Spratlys, discouraging aggressive PLAN maneuvering despite Vietnam’s smaller surface fleet. The Philippines, facing even greater pressure, stands to benefit even more from this deterrent effect.
Beyond lethal capability, submarines provide an intelligence advantage that the Philippines currently lacks entirely. They are not just weapons, they are sensors. Operating silently below the surface, submarines can monitor undersea communication cables, track the acoustic signatures of Chinese warships, record radar emissions, and map the patterns of militia activity without being seen or challenged. These platforms can listen, observe, and record in ways that satellites, drones, or surface ships cannot match. Nations with advanced maritime surveillance, such as Japan, routinely use their submarines to track Chinese naval movements through chokepoints like the Miyako Strait, gaining early warning of deployments long before they reach the open sea. For the Philippines, which has no underwater ISR capability at all, a submarine force would be transformative. It would create an entirely new layer of situational awareness, one that operates in the blind spots of China’s surveillance network.
Perhaps the most overlooked advantage is survivability. Surface ships are exposed to every tactic China now employs: ramming, water cannons, laser targeting, electronic interference, and relentless shadowing. They can be cut off, encircled, or physically blocked from reaching their objectives. A submarine is immune to all of that. It cannot be rammed because it is invisible. It cannot be blocked because its position is unknown. It cannot be intimidated or forced to withdraw because no ship can threaten what it cannot detect. The contrast becomes stark when looking back at historical flashpoints. During the 2012 standoff at Scarborough Shoal, the Philippines’ largest surface vessel at the time, the BRP Gregorio del Pilar, was gradually isolated and pressured into leaving the area. A submarine in that crisis would not have been forced into retreat. It could have remained on station, gathering intelligence, demonstrating presence, and shaping China’s behavior without ever presenting a visible target.
This combination of lethality, intelligence value, and survivability makes submarines unique. They are not replacements for surface ships, aircraft, or missiles, they are the cornerstone of a deterrence strategy that levels the playing field in a region where the balance of power above the water’s surface is heavily tilted toward China. For a country that faces daily pressure at sea and sits across some of the world’s most strategic maritime spaces, submarines provide capabilities that nothing else can match.
https://www.youtube.com/watch?v=7X0VG1KbQX8
A Realistic Picture of Philippines Capability
A realistic assessment of the Philippines’ maritime capability begins with the numbers, and those numbers paint a picture of a country finally investing in external defense after decades of underfunding. The 2025 defense budget stands at ₱256.1 billion, roughly US$4.38 billion, the highest allocation in the nation’s history. It reflects a growing recognition that the challenges in the West Philippine Sea can no longer be addressed with legacy equipment or a purely defensive posture. Within this budget, the submarine program represents one of the most ambitious undertakings the Armed Forces of the Philippines has ever pursued. Estimated between ₱80 to ₱110 billion (US$1.4 to US$2 billion), the initiative is designed not only to procure two submarines but to construct an entire ecosystem around them: a dedicated submarine hub at Subic or Sangley, full training pipelines, maintenance facilities, long-term logistical support, and a technological foundation capable of sustaining an undersea force for decades.
To understand the significance of these figures, it is necessary to compare them with the country’s neighbors. Vietnam operates six submarines, all Russian-made Kilo-class boats that have reshaped power dynamics in the Spratlys. Indonesia maintains four, with ongoing modernization plans, while Singapore fields four highly advanced submarines and has four next-generation Invincible-class vessels on the way, making it the region’s most capable undersea operator. Even Malaysia, despite its smaller maritime footprint, maintains a pair of modern submarines that complicate external interference in its waters. In stark contrast, the Philippines, the state facing the most intense daily pressure from China, has zero. No undersea capability. No submarine-trained crews. No deterrent presence beneath its waters.
This imbalance shows how critical the submarine program truly is. The Philippines is not trying to match China’s fleet or compete with regional powers. It is trying to close a capability gap so large that it affects every maritime decision the country makes. With no submarines of its own, Manila has no way to monitor activity below the surface, no ability to complicate foreign naval operations, and no strategic platform that can stay invisible while exerting influence. The figures reveal both the scale of the challenge and the seriousness of the response. For the first time in its modern history, the Philippines is preparing to build an undersea force, not to seek parity, but to ensure that its maritime rights are backed by real, credible capability.
Philippines Calls on the World to Stop China’s South China Sea Grab
Supplier options – The Strategic Consequences of Choices
Choosing a submarine supplier is more than a technical decision for the Philippines, it is a geopolitical alignment, a long-term strategic partnership, and a commitment that will shape the nation’s defense posture for generations. The country is not simply buying vessels; it is selecting an entire ecosystem: training, basing, logistics, maintenance, technology transfer, and political relationships. Each potential supplier brings a different set of advantages and a different strategic direction, making the choice as consequential as the submarines themselves.
France stands out with its Scorpène-class offer, one of the most widely adopted diesel-electric submarines in the world. What makes the French proposal particularly compelling is that it goes beyond selling hardware. Paris offers a complete submarine ecosystem, full training pipelines, long-term maintenance support, and financing options that allow Manila to spread costs across years rather than absorbing the burden immediately. The French have also proposed establishing a permanent submarine support facility in Subic, effectively turning the port into a regional hub for undersea operations. Scorpène submarines have already proven their value in India and Brazil, two countries that built modern undersea forces around the platform. For the Philippines, partnering with France would mean aligning with a European power seeking a deeper role in the Indo-Pacific and gaining a partner known for long-term defense commitments without the geopolitical strings attached by other major powers.
South Korea offers a different kind of appeal. Its KSS-III PN or Ocean 1400PN submarines represent some of the most modern and capable diesel-electric boats available, equipped with Air-Independent Propulsion systems that allow longer submerged operations. Seoul’s advantage goes beyond technology: Korea is already one of the Philippines’ strongest defense partners, supplying FA-50 fighter jets, new-generation corvettes, and various naval assets. This existing relationship means interoperability, training familiarity, and a high level of trust are already established. Korean submarines are designed with compatibility in mind, making them easier to integrate into a regional security environment aligned with Japan and the United States, two of the Philippines’ most important strategic partners. Choosing Korea would reinforce an already solid defense relationship and anchor the country more firmly within the broader network of Indo-Pacific alliances.
Spain’s S-80 Plus introduces an entirely different dimension. As the largest and most advanced option among the contenders, it promises exceptional endurance, deeper diving capability, and state-of-the-art combat systems. The S-80 is not merely an incremental improvement, it represents a leap into the upper tier of non-nuclear submarine technology. Opting for this platform would signal that the Philippines is aiming to build a high-end undersea force from the outset. Beyond the technical factors, Spain’s offer carries geopolitical significance. Madrid has been increasing its engagement in the Indo-Pacific, and the S-80 program would create a strong strategic link between Manila and Europe’s rising security involvement in the region. Choosing Spain would anchor the Philippines to a broader European defense network seeking to balance Chinese influence in Asia.
Each option pulls the Philippines toward a different strategic orbit. France brings an independent European partnership and a fully integrated support ecosystem. South Korea delivers technological sophistication with close ties to U.S. and Japanese security frameworks. Spain offers a cutting-edge platform and a gateway to Europe’s expanding Indo-Pacific strategy. The submarine the Philippines ultimately selects will determine not just what the country operates underwater, but who stands beside it, who trains with it, who supplies it, and who shares responsibility for the maritime stability the Philippines seeks to defend. The decision is not merely technical, it is strategic at the highest level.
Real Challenges – Beyond Buying the Submarines
Acquiring submarines is only the first step in what will be one of the most complex military transformations in Philippine history. The real challenge begins after the purchase, because an undersea force is not just a collection of vessels, it is a sophisticated ecosystem that must be built from the ground up. The Philippines is starting with zero experience in submarine operations, meaning every part of the capability must be created entirely from scratch. That includes developing doctrine tailored to the country’s archipelagic geography, writing operational procedures for deep-sea patrols, building safety and rescue protocols for emergencies, and establishing an undersea command-and-control structure capable of coordinating submerged assets with surface ships, aircraft, and allied surveillance networks. Training pipelines must also be formed, producing sailors who can meet the grueling psychological and technical demands of submarine service. Other nations show how long this process can take: India, for instance, spent nearly a decade mastering the full operational cycle of its first Scorpène submarine, despite having decades of prior exposure to undersea warfare. The Philippines will face a similar learning curve, compressed into an even tighter timeline.
Maintenance presents an equally serious challenge. Submarines are among the most maintenance-intensive weapons systems in the world, requiring dockyards with specialized workshops, highly trained engineers, constant parts procurement, and strict adherence to safety inspections. The consequences of inadequate maintenance can be catastrophic. Indonesia’s KRI Nanggala, which sank in 2021 with all 53 crew members aboard, became a tragic reminder that the margin for error in submarine operations is razor-thin. Investigations pointed not only to aging systems but to lapses in the long-term support structure required to keep a submarine fully mission-capable. For the Philippines, building a maintenance ecosystem will demand sustained funding, new technical expertise, and continuous oversight. A submarine force cannot succeed with occasional attention, it requires an enduring national commitment.
Political continuity is another major factor shaping the program’s future. Defense modernization in the Philippines has often been disrupted by leadership changes, budgetary shifts, and shifting political priorities. Submarine development cannot survive on enthusiasm alone; it needs long-term consistency across administrations. A single misaligned budget cycle, a change in political climate, or external pressure from influential actors could delay or even derail progress. Ensuring stability in funding, vision, and policy direction will be just as important as choosing the supplier or training the crews. Submarines take years to build, more years to master, and decades to maintain, making political steadiness as crucial as the hardware itself.
These challenges show a critical reality: creating an undersea force is not simply a procurement project, it is a generational transformation. The cost is high, the learning curve steep, and the risks significant. But the payoff, in terms of deterrence, sovereignty, and national security, is equally profound. Overcoming these obstacles will determine not only whether the Philippines can operate submarines, but whether it can unlock their full strategic value in an increasingly hostile maritime environment.
https://indopacificreport.com/can-the-philippines-be-the-worlds-next-big-tech-hub/
Regional and Alliance Benefits
The strategic value of a Philippine submarine fleet extends far beyond national defense, it strengthens the entire security architecture of the Indo-Pacific. Submarines would immediately elevate the Philippines’ role within the first island chain, the arc of territory stretching from Japan to Southeast Asia that is central to regional deterrence against China. Operating silently beneath these waters, Philippine submarines could integrate directly with the undersea networks of the United States, Japan, and Australia, allowing the country to participate in advanced anti-submarine warfare coordination, secure data-sharing, and multilateral maritime exercises. These allies maintain some of the world’s most capable sonar systems, P-8 Poseidon aircraft, and undersea surveillance networks. By joining this architecture with its own submarines, the Philippines would gain access to a level of shared intelligence and operational synergy that surface ships simply cannot provide. It would no longer be just a location on the map, it would be an active undersea partner within the first island chain’s defensive backbone.
A submarine force would also transform how the Philippines is perceived by its allies. Instead of relying solely on external security guarantees, Manila would demonstrate a willingness to shoulder part of the strategic burden. Submarines convey seriousness: they require discipline, commitment, and a long-term vision that signals a country is intent on defending its maritime rights rather than outsourcing them. This shift would carry real diplomatic weight. For example, with submarines in its arsenal, the Philippines could join trilateral patrols with Japan and the United States in the Bashi Channel, a critical chokepoint linking the South China Sea and the Pacific. Participation in such missions would boost deterrence, expand maritime domain awareness, and strengthen the cooperative security framework that regional stability increasingly depends on.
In this way, the benefits of a Philippine submarine force extend far beyond deterrence against China. It integrates the country into the region’s most sophisticated security partnerships, enhances its credibility among allies, and gives Manila a greater voice in shaping Indo-Pacific stability. The result is a stronger Philippines, a stronger alliance system, and a more resilient regional balance at a time when it is needed most.
https://indopacificreport.com/philippines-southeast-asias-economic-giant-set-to-soar-by-2039/
Possible Outcomes – What the Next Decade Could look Like
Over the next decade, the Philippines’ submarine ambition could take several dramatically different paths, each shaping the country’s maritime future in profoundly different ways. In the most promising scenario, the vision becomes reality. By the early 2030s, perhaps between 2031 and 2033, the first Philippine submarine entered active service. Armed forces personnel, after years of rigorous training abroad, return as some of the nation’s first undersea specialists. A submarine hub rises in Subic or Sangley, complete with simulators, workshops, and the infrastructure needed to sustain consistent operations. Once deployed, the submarines provide the country with a level of deterrence it has never possessed, quietly patrolling strategic areas and complicating any foreign movement that threatens Philippine waters. This breakthrough forces a broader shift in defense planning, accelerating investments in maritime patrol aircraft, anti-submarine warfare helicopters, fixed underwater sensors, and long-range surveillance networks. By the late 2030s, the Philippines wasn’t just catching up, it was establishing itself as a credible undersea player in Southeast Asia.
A second, less optimistic path is one in which submarines do arrive, yet fail to reach their full potential. This is the “paper fleet” outcome: impressive vessels on the outside, but without the deep, sustained ecosystem required to operate them. In this scenario, crews remain undertrained due to limited slots abroad or delayed local training facilities. Maintenance cycles fall behind schedule, funding becomes inconsistent, or technical issues go unresolved. The submarines become more symbolic than functional, showcased during events and declarations but rarely deployed for real missions. Other nations have experienced this trap before, acquiring advanced assets without the long-term institutional backbone to support them. The Philippines, without consistent investment and disciplined management, could face the same risk. The dream would exist on paper, but not in practice.
The third scenario is the most disappointing but cannot be dismissed: the program may be delayed well beyond its intended timeline, possibly into the 2040s. Political transitions, shifting priorities, budget reallocations, or external pressure could slow progress to a crawl. Modernization programs in the Philippines have historically faced interruptions, and submarines, being complex, costly, and politically sensitive, are particularly vulnerable to delays. The result would be another decade of strategic vulnerability, with the country watching as neighbors expand their undersea capability while it remains without one. In this future, the Philippines continues to confront growing pressure in the West Philippine Sea with the same limited tools it has today, relying heavily on allies and losing the opportunity to build its own independent deterrent.
These scenarios reveal the stakes of the submarine program. Success demands steady funding, long-term political commitment, technical discipline, and deep cooperation with experienced partners. Failure, whether through mismanagement, underinvestment, or delay, would leave the Philippines exposed in a region where undersea capability is fast becoming the standard. The next decade will determine whether submarines become a transformative pillar of national defense or another strategic opportunity lost.
End Words – Submarines are not a Choice, They are an inevitability
The trajectory of regional security in the Indo-Pacific leaves the Philippines with little doubt about what must be done. China is expanding its maritime power at a speed unmatched by any nation in modern history, launching warships, coast guard vessels, and militia elements at a rate that reshapes the balance of power year after year. For the Philippines, a country situated at the center of this strategic arena, relying solely on surface ships is no longer sustainable. Surface vessels, no matter how modern, remain visible, trackable, and vulnerable to the very tactics China now employs with increasing confidence. They can be blinded, blocked, rammed, or harassed in ways that undermine their ability to assert presence or defend territory.
Submarines change that reality. They introduce uncertainty into an environment China currently controls with overwhelming advantage. An undersea force provides the Philippines with an invisible shield, one capable of gathering intelligence, complicating adversary planning, and quietly deterring escalation without being exposed to coercion on the surface. Their presence need not be advertised; their value lies in the doubt they create, the risk they impose, and the strategic caution they force even on a much stronger navy.
For the Philippines, pursuing submarines is not about prestige or symbolic modernization. It is a recognition of geography, vulnerability, and the harsh realities of the West Philippine Sea. Building an undersea capability marks a turning point, one that signals a shift from reactive defense to proactive deterrence. It marks a moment where the country decides not to accept its disadvantage as permanent, but to redefine its position as a true maritime nation capable of guarding its waters with strength, resilience, and modern capability.
In the end, submarines are not merely a military purchase. They are a declaration that the Philippines intends to secure its maritime future, protect its sovereignty, and stand its ground in one of the most contested seas in the world. They are not a luxury. They are an inevitability.
