When Brett Devereaux wrote his Fremen Mirage posts early in 2020 I made some notes about warfare between Great Houses in the Dune books. The release of the trailer for the new Dune movie inspired me to turn these into something more organised.
Warfare in Dune, the first three books in particular, is unusual in science fiction. Many science fiction books, and every movie or TV show I've seen, depicts future warfare as an extension of the 20th century. Ground forces are disciplined infantry and armoured fighting vehicles with high velocity projectile weapons or some kind of laser. Spaceships fight like battleships or aircraft carriers depending on the writer's preference as to how the tech tree develops.
Dune has aristocrats and their retainers fighting hand to hand with swords and knives. Ornithopters (light aircraft that have flapping rather than fixed wings) act as troop transports and for reconnaissance, but don't engage in dogfights. Spaceships are also just for transporting troops and don't fight each other. It's all very medieval.
And this seems to confuse or upset the authors who have extended Dune with new books or written scripts for movies and TV. The Prelude to Dune series of books by Frank Herbert's son and Kevin Anderson have lots of laser fire and battles in air and space. The first Dune movie and the SciFi channel miniseries likewise had energy weapons and guns. Can't be science fiction without lasers, right?
Which to me is very disappointing. Science fiction at its best asks how we'll change and do things differently, not just linear extrapolation from now. Why do the Great Houses of the Imperium in Dune fight the way they do?
This discussion is focussed on the first three books: Dune, Dune Messiah, and Children of Dune. The Dune universe changes dramatically after that, and warfare does too.
I'm not going to analyse in too much detail how the weapon systems work, because that's already been done by Daniel Duffy. In particular, I'm not going to question whether the science and technology of Dune are actually possible. This is an in-universe discussion, accepting that Holtzman fields and the other gadgets all work as described.
My argument is that Dune warfare can only exist because of three factors:
Shields, the defence against projectiles and lasers.
The Butlerian Jihad, the prohibition on artifical intelligence.
The Imperium, the aristocratic ruling class that controls society.
Take away any of these and the distinctive style of warfare in Dune would no longer be practical.
In Dune these are a Holtzman force field used as defence. A shield can be set to block any moving object above a certain velocity. This works in both directions, so a shield that stops bullets coming in also stops you from shooting out.
Shields are usually personal, protecting one individual. (It is not practical to tune the shield to block all moving objects, because that would stop the movement of air molecules in and out of the shield and you would suffocate.) Shields are also common on vehicles, for example ornithopters. Entire buildings can be shielded, such as the Ducal palace on Arrakis, and also building sized spaceships on the ground, but this seems less common.
Shields are the ultimate in knightly armour. Warriors with shields are immune to all the missile weapons that defeated knights historically. With no longbows or muskets or machine guns, shielded infantry fight each other hand to hand, and skill with melee weapons is all important. An elite force of aristocrats and their trained retainers will slaughter a much larger number of unshielded or poorly trained fighters.
For the same reason there are no tanks in Dune, no heavy artillery. Big guns are no better than hand held guns, so vehicles are only useful to move infantry around. On Caladan and Arrakis ornithopters are superior to ground transport, but other planets might use light wheeled vehicles as infantry troop carriers.
The books do suggest that shields don't protect entirely against very powerful kinetic impacts. In the deserts of Arrakis shields are useless, because sandworms will kill the wearer. So it is possible to collapse a shield with enough force, or maybe just bounce it around so hard that the person inside is injured or killed like an egg inside an unpadded box. But sandworms are big, really big, suggesting that the amount of kinetic energy required to kill one shielded warrior would be at least an entire salvo of battleship guns.
Lasers
Lasers - lasguns in Dune terminology - are a special case. Firing a laser at a shield creates an explosion of unpredictable size ranging up to small atomic level. And feedback, reflected energy of some kind, destroys the laser as well.
(No, I have no idea why. It's science fiction, and I'm accepting that in the universe of Dune this it what happens. Perhaps visible light / EM radiation always generates some feedback, but without the coherence of a laser beam it is too scattered to be harmful.)
This makes lasguns impractical. Warriors and professional soldiers generally will not want to risk killing themselves every time they pull the triggger. And in Dune, like in our current world, atomic weapons or what look like atomic are a line no-one wants to cross for fear of retaliation.
That said, I assume that a world such as the Harkonnen home planet of Geidi Prime has a number of desperate people with nothing to lose. A shipment of smuggled lasguns could create some impressive damage.
This is, by the time of Dune, the long-ago crusade against machines that think, or as perceived as being capable of performing similar functions to the human mind. It is a thoroughly ingrained moral and religious prohibition.
So the Imperium has no computers. No autopilots or homing missiles or autonomous drones.
This prohibition prevents some possible weapons that could be used against shielded infantry. In Dune, the Harkonnens try to assassinate Paul with a tiny flying poisoned needle, remotely piloted.
With artificial intelligence, even in the limited computer forms of today, these would be deadly. Flood the battlefield with artificial poison wasps, each with an on-board computer that searches for a target and adjusts its speed as necessary to penetrate the shield.
A second example is from Dune Messiah. Alia trains against a mechanical / electronic sword fighting "target" which could kill her if she makes a mistake. (That this even exists suggests that the most privileged members of the Imperium can ignore the Butlerian Jihad prohibition to some extent, provided they don't get caught.) With AI these could become the Terminators of Dune.
Without AI the flying poison needles would be very labour intensive, each requiring a human pilot. Still, the ability to kill your opponent without needing to be close enough for them to hurt you has always been appealing, so why aren't these in use on battlefields as well? Which leads us to the third, equally important factor.
The Dune Imperium is ruled by an Emperor and Great Houses who have nothing to gain and much to lose by warfare becoming less medieval, less dominated by elite hand to hand fighters.
These are not nice people. Frank Herbert himself was well aware of this, pointing out that Leto Atreides may be benevolent, but he's still an absolute dictator. The Atreides on Caladan and then Arrakis may be good rulers, but not because there is a requirement or obligation to be so. The Harkonnens are not breaching any Declaration of Human Rights with their atrocities and oppression.
It is said that during the medieval Hundred Years War between England and France, the King of France wanted to teach the commoners to use longbows like the English. This was blocked by the French nobility, who knew that French longbows could just as easily be used against them once the war was over.
Whether this actually happened doesn't really matter. The medieval writers recognised the conflict of interest, and this same conflict is present in Dune. The current style of warfare benefits the emperor and nobles. They have no motivation to overthrow the system that makes them rich and powerful, and thus no reason to fund or support research and development into new weapons. They are however strongly motivated to crush any upstart or outsider looking to innovate.
The frozen structure of the Dune Imperium, and its unique style of warfare, lasts for many thousands of years.
Fortunately for humanity as a whole, the Imperium is overthrown by Paul Muad'Dib. The Golden Path of the God-Emperor Leto II then destroys the remnants, and the Scattering after his death creates new external enemies far more dangerous than the English were to the French.
Warfare in the pair of novels Heretics / Chapter House of Dune has become very different. Shields have long been considered obsolete, and when brought back are not for defence, but as the equivalent of explosive mines and traps. There is combat in space, and spaceships use what seem to be computers. Ground and air warfare uses long range weaponry and armoured vehicles. Combat is now on a larger scale and more destructive. Warfare has become more democratic, more industrial, and in the universe of Dune this is an improvement.
There are many Dune books, and many more non-fiction books and articles about Dune. Here are three of the most interesting for this topic.
An Analysis of Warfare & Technology in the Dune Universe Daniel Duffy
The Fremen Mirage Bret Devereaux
Frank Herbert Tim O'Reilly