Future Conflicts and the Growing Importance of Military Reserves

 

Introduction

Recent conflicts in Europe and the Middle East have revived a fundamental strategic question: what kind of armed forces are required for future wars?

For decades, many Western states assumed that future conflicts would be short, technology-driven and fought by small professional forces. However, recent foresight studies within NATO and partner countries suggest a different trajectory.

One interesting synthesis of these studies was recently highlighted by Norbert Gehrke, who reviewed one hundred foresight reports on the future character of conflict produced by NATO countries, partners, and competitors. 

The emerging picture is clear: future conflicts will be faster, more complex, and potentially longer than expected.

For military planners this has a direct implication: the importance of reserves is increasing again.

 

What the Studies Say About Future Conflicts

The foresight reports reviewed in the analysis converge on several common observations about the character of future conflicts.

1. Warfare is becoming multi-domain

Future conflicts are expected to occur simultaneously across multiple operational domains: land, air, maritime, cyber, space and information environment. Military operations will increasingly depend on digital networks, satellites, and data-driven command systems.

2. The “grey zone” will expand

Competition between states will not begin with open warfare. Instead, conflicts will evolve through hybrid and grey-zone activities, including cyber operations, information warfare, economic pressure and sabotage and influence operations. Modern conflict therefore blends military and non-military instruments into a single strategic campaign. 

3. Technology accelerates warfare

Artificial intelligence, autonomous systems and unmanned platforms will dramatically increase the speed of decision-making and combat operations. In some cases, military operations may occur at machine speed, reducing the time available for political and military decision-makers.

4. Conflicts may last longer than expected

Despite technological change, recent wars demonstrate that industrial capacity, manpower and endurance remain decisive factors. The war in Ukraine has shown that high-intensity warfare between industrialized states can become a prolonged war of attrition.

The Strategic Implication: Reserves Matter Again

While the foresight reports emphasize technology and multi-domain operations, their implications point toward a more traditional requirement: depth and endurance in military forces. Professional forces alone rarely provide sufficient manpower for prolonged or large-scale conflicts. This reality is leading many countries to reconsider the role of reserves.

 Three Key Requirements for Future Military Reserves

1. Size: Strategic Depth

Future conflicts require reserves that provide mass and strategic depth. Professional forces can handle the initial phase of conflict, but reserves are required for: reinforcement of combat units, territorial defence, protection of infrastructure and long-term rotation and replacement.

A layered reserve structure is increasingly common:

Reserve Layer	Purpose
Immediate reserve	Rapid reinforcement
Operational reserve	Sustain ongoing operations
Strategic reserve	Long-term mobilization

2. Readiness: Speed of Mobilisation

The value of reserves depends not only on their size but also on their mobilisation speed.

Modern reserve systems therefore emphasize regular training cycles, pre-assigned units and equipment, digital mobilisation systems, and integration with active forces.

The difference between mobilisation in days rather than weeks can determine operational success.

3. Capability: Beyond Traditional Infantry

Future reserves cannot consist solely of traditional infantry forces. Modern defence systems increasingly require specialised reservists in fields such as cyber defence, electronic warfare, intelligence analysis, drone operations and logistics and infrastructure protection. In many countries, the civilian workforce already contains these capabilities. A modern reserve system allows the military to access them when needed.

A New Force Model Is Emerging

Across many Western countries a similar force structure is gradually reappearing:

·       A small professional force supported by a large, capable reserve.

·       The professional component provides immediate response, high readiness, and expeditionary capability

·       The reserve component provides mass, endurance, and societal resilience.

This model reflects a basic strategic reality: national defence is a whole-of-society effort.

Conclusion

Future conflicts are likely to be technologically advanced, multi-domain and strategically complex. Yet one conclusion appears increasingly clear.

Despite rapid technological change, manpower, resilience, and strategic depth remain essential elements of military power.

For this reason, reserves are not a legacy of the past. They are becoming a central pillar of future defence systems.

Source

Norbert Gehrke: Future of Conflicts – Analysis of NATO and partner foresight studies. https://www.ndc.nato.int/future-of-conflicts-a-vision-of-what-is-to-come/