War is changing, and for small states with limited populations, this transformation is not a distant abstraction but a direct strategic challenge. The character of war today is shaped less by massed armies and territorial conquest, and more by precision, persistence, and pressure across multiple domains. Cyber intrusions, information warfare, economic coercion, grey-zone operations, and long-range precision strikes have lowered the threshold for conflict while expanding the battlespace beyond traditional frontlines. For small states, such as Singapore and Brunei, these shifts demand a fundamental rethinking of defence, deterrence, and national resilience.
Historically, small states compensated for demographic and geographic constraints by relying on diplomacy, alliances, and international law, and where possible, maintaining credible conventional forces to raise the cost of aggression from hostile actors.
That logic still holds, but it is no longer sufficient. The changing character of war blurs the line between peace and conflict, military and civilian, internal security and external defence. For small states, whose societies, economies, and critical infrastructure are tightly interconnected, vulnerability is not measured only by troop numbers but by systemic exposure.
Technology further complicates this equation. While advanced systems such as drones, AI-enabled surveillance and precision weapons can offset manpower constraints, they also democratise threat capabilities. Non-state actors and weaker adversaries can now punch above their weight, exploiting commercially available technologies. For small states, technological dependence creates both advantage and risk.
Two Southeast Asian countries, Brunei and Singapore, provide good examples of how the changing character of war has an impact on small states.
With a small population, natural resources, and a modest military, Brunei’s traditional security approach has emphasised internal stability, diplomacy, and defence partnerships, particularly with the United Kingdom and regional neighbours. For decades, this posture was well suited to a relatively benign environment. However, the changing character of war challenges some of these assumptions.
As hybrid threats grow more prevalent, Brunei’s exposure lies not in invasion scenarios but in disruption, whether through cyber sabotage with significant economic loss, or information operations that exploit social cohesion and governance legitimacy.
For small states like Brunei, the challenge is not to replicate the military mass of larger powers, but to deny adversaries easy avenues of coercion. This requires a shift from force-centric defence planning to threat-centric and systems-based thinking. Even modest investments in cyber defence, intelligence fusion, and inter-agency coordination can significantly raise the cost of grey-zone operations.
With a population of fewer than half a million, Brunei’s limited manpower further constrains its ability to expand conventional forces, therefore increasing the importance of technological substitution and the development of niche capabilities.
Maritime domain awareness, cyber security, and protection of critical energy infrastructure are some key aspects that are central to national defence. Brunei’s leadership recognises the breadth and complexity of security challenges that the small kingdom faces, as reflected in the 2021 Defence White Paper. The document identifies multi-domain exploitation as a key threat to national security and underscores the need for the government to maintain flexible and adaptable capabilities to address a wide spectrum of threats.
To deal with a wide spectrum of threats, Brunei has built up defence capabilities beyond the military. For example, it has invested in cyber security institution but also pushes closer cooperation between government agencies to deal with common cyber threats. Cyber Security Brunei (CSB), as the national cyber security agency, works closely with the Royal Brunei Police Force to counter cyber threats.
Singapore offers one of the most advanced responses to the changing character or war. With a limited population and no strategic depth, Singapore has long accepted that deterrence must be comprehensive rather than purely military. Its defence posture is built on a technologically sophisticated armed force, underpinned by universal national service.
Yet what distinguishes Singapore is how it has expanded defence thinking beyond the battlefield. The concept of Total Defence, encompassing military, civil, economic, social, digital, and psychological dimensions, reflects a recognition that future conflicts will target society as much as soldiers.
In an era where cyberattacks can disrupt ports, financial systems, and power grids, Singapore’s emphasis on digital defence is particularly relevant. A small state that functions as a global hub cannot afford prolonged disruption without strategic consequences, be it on the economic front or domestic stability.
By integrating the private sector, civil agencies, and the public into national security planning, Singapore mitigates a core vulnerability of small states: over-reliance on a narrow set of critical nodes. The lesson is clear, resilience, not just firepower, is now a key currency of deterrence.
Both Brunei and Singapore illustrate a broader truth: population size increasingly shapes not the ability to fight wars, but the margin for error. Small states have little tolerance for strategic surprise, prolonged disruption, or internal fragmentation. The changing character of war magnifies this reality by compressing decision-making timelines and targeting civilian morale and economic confidence.
The strategic response, therefore, lies in integration. Defence must be integrated across domains, agencies, and society. Diplomacy must reinforce deterrence, and partnerships must be operational rather than symbolic. Singapore’s deep defence relationships with major powers and regional neighbours, and Brunei’s reliance on trusted security partners, both underscore the enduring importance of external balancing for small states. Yet partnerships cannot substitute for internal preparedness.
Ultimately, the changing character of war does not render small states helpless; it simply changes the rules of survival. Those that adapt by investing in resilience, embracing whole-of-nation approaches, and anticipating non-traditional threats can remain secure despite demographic limitations. Those that cling to narrow, conventional definitions of defence risk discovering that modern conflict rarely announces itself with tanks at the border.
For small states, the future of security will not be decided by size alone, but by adaptability, cohesion, and strategic foresight. Brunei and Singapore, in different ways, show that even with limited populations, survival in a contested world remains a matter of choice as much as circumstance.
