How will the future of war be fought? It is the perennial dilemma for defence planners and military personnel. Currently, there is a debate in the West’s defence establishments between advocates of a futuristic digitised battle space, where everything is integrated in a single electronic grid, and the sceptics, who look at past wars and the follies of former futurists.

The advocates of a futuristic force claim that only by adopting new technologies will the West retain its advantages over any threatening state: failure to keep up with new tech risks defeat. They argue that the only effective approach is to construct a truly integrated system across all domains of land, sea, air, space, and the informational-electronic environment. The sceptics in the defence establishments present events in Ukraine and other recent conflicts as evidence that war has hardly changed. It is still a matter of human resilience and determination, skilful manoeuvres and firepower. They maintain that in warfare things always go wrong, so robustness is more important than new technology. They state that the complexity of multi-domain integration is its undoing.

The animated and graphical representation of multi-domain integration presented in military videos and colourful brochures is exciting and confident. Military personnel have been concerned about the problem of anti-access and area denial (known as A2/AD) weapons that can destroy Western forces long before they can get close to a hostile adversary, and the multi-domain scheme seems to offer a solution. Having identified and digitised every single item in the landscape in an electronic grid, the advocates claim they can summon whatever is required to burst an A2AD ‘bubble’, and, even more astonishingly, that their fully autonomous weapons will ‘talk’ to each other without humans in the loop, except to issue the final executive order to release ordnance.

It is a combat environment that extends from outer space to the depths of the oceans and across the surface of the globe. It suggests that warfare will accelerate, as targets are identified and engaged in milliseconds, with human operators limited to either a directing role or in small numbers on the ground as human-machine combat teams. Logistics will be fully automated too, with drones and unmanned aircraft delivering munitions and supplies on a just-in-time basis, like a modern supermarket or product distribution centre.

Given the sheer scale of the operations, it is thought that artificial intelligence will be vital to maintain control of all the communications and data available and prevent human commanders being overloaded. Advanced networking technologies would also be vital to ensure the flow of data. While there is a massive harvesting of observed, cyber and space datasets, artificial intelligence will, it is assumed, fill the gaps where those data are incomplete.

Advocates argue that the West will enjoy massive advantages. It envisages ‘expanded manoeuvre’, a term used to describe being able to anticipate the actions and direction of the adversary and placing one’s own forces to take advantage of them.

The tempo of multi-domain operations is a distinctive feature. Unlike wars of the past, with episodes of intensity interspersed with pauses to reorganise and recover, the promise of the multi-domain operation is of continuous and unrelenting activity. There is constant acquisition of targeting data and adaptation to situations. The literature on multi-domain operations emphasises its ability to create multiple dilemmas for the enemy, but it also suggests that the adversary would be overwhelmed and exhausted by relentless pressure, heavy losses, and unexpected developments.

Beneath the surface, the epistemology of multi-domain integration reveals a combination of fear and opportunity. There is a fear of obsolescence, of the superiority of rivals, and that new technological developments are occurring so quickly that no one can keep up. The fear of this disruptive technology is that it could bring to an end the culture and ethos that the armed forces prize. The bond pilots enjoy with their supporting ground crew would be terminated by purely robotic craft. The ship’s company and its captain would be transformed beyond recognition by sole reliance on automated ships and missiles. The army would not be organised by the close-knit unit but consist only of technicians and remote decision-makers. On the other hand, advocates are eager to seize the opportunity afforded by new technologies. Always eager to acquire an advantage over the adversary, Western defence planners are also particularly keen to find ways to reduce casualties, and technology is considered critical in this regard.

As humans, we are programmed to assume our solutions will work. It is an important evolutionary trait. The military solution to this optimism bias is to assert deductive reasoning and the arrangement of a reserve capacity, to compensate when systems fail, resources run out, or solutions are exhausted. Multi-domain integration has not yet been tested, and there is some doubt whether it would work in practice. There is a fear of abandoning what we know to work.

When we are confronted with novel problems, we usually seek to affirm potential solutions by three means: to imagine (that is, to hypothesise), analogise, and compare.

Multi-domain integration can be imagined. It is often portrayed through animations and diagrams, complete with dramatic voiceovers and music. The hypothesis is strong in theory, but sceptics are more concerned with harsh realities. They ask: what happens when it goes wrong?

Analogies are often framed as questions too. Is it like submarine and anti-submarine warfare, with a dependence on electronic rather than physical means of detection and fighting? Is it like the transition between horses and tanks in the early twentieth century, where the obsolescence of one technology in favour of another is stark and obvious? Advocates depend on the novelty of new technologies, but sceptics prefer comparisons with the past, and warn of historic failures. Is multi-domain integration the equivalent of a Maginot Line: the state of the art in defensive technology but easily bypassed by a nimble adversary?

The third approach to consider leads us to the following question: is it comparable to what happened in Nagorno-Karabagh in 2020 or the Russian invasion of Ukraine in 2022? Sceptics would point out that the war in Ukraine looks very much like past wars, while advocates argue that the conflict just makes the case for multi- domain even stronger.

The reality of war still matters. War demands robustness and there is genuine concern that the filigree of networks on which multi-domain operations depend are vulnerable to destruction, through conventional fighting, human failures, or an electromagnetic pulse following nuclear detonation. Despite the emphasis on the different domains, in reality war has a single operational dimension. It matters little where firepower or communications reside, but it matters a great deal whether they are available and where they are being directed.

Above all, war is more than battles and operations. Regardless of the technology, it is, as Thucydides reminds us, the human aspects that matter most. If the public embrace the desire to fight to survive, are willing to endure and sacrifice, then systems will become less important. Even where superior and overwhelming firepower is employed, if a population refuses to submit, they will endure defeats in battle and keep fighting. Multi-domain integration determines only how to fight; it will not necessarily determine who wins wars.