Rethinking deterrence beyond land, sea, and air

Defense security used to be immensely simpler. In the past, it meant protecting a country’s territorial integrity across land, air, and sea. Depending on the domain, the Philippine Army, the Philippine Air Force, and the Philippine Marines had clearly delineated roles.

But times are rapidly evolving. Threats are no longer confined to the three common domains. Technology has driven great changes in the way nations maintain and protect their borders.

Cyberspace has emerged as an important new domain in modern defense and security. States seeking to antagonize others or advance their interests at the expense of the established international order increasingly rely on sophisticated digital tools to do so. These cybersecurity threats can target individuals, organizations, critical infrastructure, and nations. The consequences range from financial losses, to breaches of privacy, damage to reputations, and the theft of sensitive information. When critical infrastructure is attacked, the effects can be especially severe, causing widespread disruption.

During last week’s forum called “Building Credible Deterrence Through a Multi-Domain Armed Forces of the Philippines Modernization,” organized by the Stratbase Group in partnership with the Konrad-Adenauer-Stiftung (KAS) Philippines, Armed Forces of the Philippines (AFP) Chief of Staff General Romeo Brawner, Jr., through a message delivered by Acting Deputy Chief of Staff and Commander of the Civil-Military Operations Command Lieutenant General Arvin Lagamon, emphasized that “a credible deterrent posture requires an AFP that can think, adapt, innovate, and operate in emerging domains of warfare.”

This is why the “cyber domain has become a major area of focus.” Recognizing this reality, the AFP continues to strengthen its cyber capabilities and is pursuing a more robust cyber command structure.

Yet strengthening deterrence across multiple domains also requires confronting the long-standing constraints surrounding AFP modernization. Major General Ivan D. R. Papera, Chief of the AFP Systems Engineering and Modernization Office, acknowledged during the same forum that years of limited budgets forced the military into a “piecemeal approach” to capability acquisition, often resulting in interoperability challenges from what he described as “chop suey” procurement from different countries.

As the Philippines approaches the 10^th anniversary of the landmark 2016 arbitral ruling amid an increasingly contested Indo-Pacific region, credible deterrence will depend on its ability to secure all domains — not only those visible above the surface, but also those hidden beneath it.

Amid international reports of subsea cable-cutting incidents and local reports of underwater drones with Chinese markings discovered in various parts of the Philippines, it is becoming increasingly clear that the submarine domain represents the next strategic frontier that underpins national security, economic stability, connectivity, and regional trade.

As an archipelagic state located at the center of vital maritime routes in the Indo-Pacific, the Philippines cannot afford to neglect what happens beneath the surface. The Philippine Seas also serve as home to submarine cables that connect major economic players such as the United States, the European Union, Japan, and many others. These submarine cables form part of the invisible infrastructure that powers the global economy. They carry financial transactions, internet traffic, government communications, military communications, and critical data flows that sustain modern societies and economies.

These developments are happening faster and with greater coordination. Vulnerability in one domain can quickly create risks in another. For an archipelagic nation like the Philippines, understanding and protecting what happens beneath the surface is imperative.

Fortunately, the Armed Forces has long acknowledged that it has to step up to meet the challenges of the times. The modern battlefield is now multi-domain, highly technological, and constantly evolving, demanding faster, more integrated, and more adaptive defense capabilities.

Foremost, the AFP launched the Comprehensive Archipelagic Defense Concept reflecting the pivot to external defense, allowing it to defend sea lanes of communication and protect maritime territories more effectively.

Part of this shift is recognizing the need to invest in assets and capabilities that can strengthen the country’s awareness, monitoring, and presence in the underwater domain. Investments in submarines, underwater surveillance systems, maritime domain awareness technologies, and undersea infrastructure protection capabilities should increasingly become part of the country’s long-term modernization agenda.

Mr. Papera also pointed out that modernization should not be viewed merely as an expense, but as an investment in the country’s long-term security and deterrence capabilities. This is especially important as the AFP seeks to move beyond simple procurement toward more integrated capability development across multiple domains.

It is here that the necessity of collaborating with like-minded nations becomes paramount. We have too many competing priorities and remain constrained by financial and technical limitations. It is reassuring that our military leadership remains fully aware of these evolving threats and is mindful of the need for constant retooling and modernization.

More importantly, however, we must not allow ourselves to be distracted from this aim. More than the personalities that dominate the issues of the day, remaining conscious of geopolitical dangers and defending what is ours across all domains is a fundamental responsibility we owe to our people and our nation.

Victor Andres “Dindo” C. Manhit is the president of the Stratbase ADR Institute.