What would cause full body armor to return?

Question

Many times in sci fi, the concept of full body armor has come up again and again. Most famously in Star Wars where we see Stormtroopers wear white armor covering their entire body.

What I'm wondering is why? Modern soldiers wear armor that only protects a small region of the upper torso and head to save on weight and have better mobility.

Why would a future military have standard issue armor that covers the entirety of the body?

Some assumptions:

• The material the armor is made of is light and strong enough that it does not burden the solider much, or at most requires assistance in either a passive/very minor assistive exoskeleton to operate with.
• Guns and projectile weapons over all are still a thing.
• Covers at least 75% of the body if not fully. Nothing is stopping use from going the way of the peasant soldier i.e. focusing on head, torso, arms and hands protection. Maybe leg armor too, if you're lucky.
• The soldiers wearing this armor are in a terrestrial environment.

Answer 1

Environmental dangers

Space is a dangerous place. You may find that you're more at risk of dying from radiation or lack of oxygen or heat than by being shot by the enemy. Sure you might get instantly obliterated if one of their ship artillery hits wherever you are on the ship but should you survive you want to be protected from dangers such as depressurization and lack of on-ship life support systems.

You will need to be protected from head-to-toe in order to be protected from most if not all environmental dangers, especially in space, which is what I'm assuming is the general environment of your setting by your use of storm troopers as example.

Answer 2

Body armor is designed to protect mostly against the type of bullets we use.

These bullets produce localized damage. They don't fly that fast. Some body parts are more vital than others. Armor is heavy and cumbersome. The enemy will aim for the center of the chest because it's a lot easier to hit than the head. So it makes sense to only put armor on the most vulnerable parts.

To justify full body armor, you'd have to change one of these parameters.

Remove the current rules of engagement and allow for poisoned bullets that kill you even if they hit you in the pinky finger... or white phosphorous, or explosive bullets... then damage is no longer localized, and most body parts become vital. In that case, you would need full body armor.

Change the enemies, for example give them acid for blood that sprays everywhere when shot.

Make flamethrowers legal! Everyone get an asbestos suit!

Fight in vacuum: any hole in the suit means a very bad day, so it has to be bulletproof everywhere.

Make aiming more accurate, for example robotic auto-aiming space pew-pew lasers that travel at the speed of light, or homing bullets that can reliably hit any non-armored part on a moving target. Then you need to armor everything.

Use the Space Shotgun instead of the space rifle. I mean, if you're shooting people inside a sci-fi spaceship you probably don't want to use .50 cal or armor piercing bullets that will go all the way through the ship and puncture the reactor confinement or just blow the air out. So you'd use space buckshot instead, which works better in close quarters anyway. If the enemy uses space shotguns that aren't armor piercing, you don't want a heavy thick chest plate because the spread of the shot means you'll get hit somewhere that isn't covered anyway. It would be better to have lighter protection and more coverage.

Answer 3

There exist already today full body armors: hazmat suits

In a scenario where the enemy can use biological, chemical or nuclear weapons, you want to avoid that those substances enter in contact with the body of the soldiers. The only solution is therefore to fully cover the body and leave 0 exposed surface.

Answer 4

One New Thing (Name Your Problem):

All you need to justify head-to-toe armor is ONE new attack form that requires armor to protect from it. It doesn't matter WHAT that is, as long as the logical defense is armor. It doesn't even have to be an attack currently in use - even knowing the enemy WILL use it if you don't defend against it will require everyone to be armored. And a suit isn't enough, because the slightest breach of the suit will kill you.

• SONIC WEAPONS: Sound weapons are developed so lethal or debilitating sound waves cripple the nervous system. Only adding vibration-cancelling protection to all parts of the body keeps out the sonic attack. If armor can be made to absorb shockwaves, this can even apply to reducing ubiquitous blast effects.
• NBC: Nuclear, biological, and chemical weapons mean chemicals, radiation and disease are able to penetrate to a man not covered everywhere. Chemicals can include things as humble as irritants. Only constant isolation protects you. Anthrax can be everywhere and new strains made to overcome the best immunity.
• INCOMPATIBLE ENVIRONMENTS: Alien worlds, ice-cold arctic winters, deep ocean, hydrochloric acid atmospheres, space, the list goes on and on.
• KILLER MICRODRONES: Tiny robots are everywhere, and out for human flesh. The armor needs to be strong everywhere to keep these evil things from finding a vulnerable spot. And perhaps you need to periodically douse in acid or flaming gasoline to kill off the things as they accumulate on your gear.

That list could go on all day. But in addition, there are other reasons to completely protect your troops.

• YOUR COST PER MAN IS INSANELY HIGH ALREADY: Each trooper requires vastly costly training and equipping to make him effective, or the men who can fight are wildly rare. Maybe 1 in 100 men is immune to mind control, or 1 in 1000 is psychic. Maybe you need a PhD to operate the linear accelerator cannons in all the possible situations. Or the effort to deliver one soldier to the battlefield costs a billion dollars (teleporters, interstellar travel). No cost compared to that is too high to assure each man is able to fight to peak efficiency.
• EVERYBODY USES POWERED EXOSUITS ANYWAY: Every man needs to operate completely independent of the supply chain or the equipment (weapons, life support) they use is too heavy to move in without an exo-suit. If you can haul 10 tons of gear, what's half a ton of ablative projectile & heat resistant plating amongst friends?
• PROJECTILE-RESISTANT OPPONENTS: If the enemy (zombies, super-armored guys, shock-resistant aliens, robots) is resistant to small penetrating projectiles and the tissue shock that goes with it, they might close to melee range without being substantially slowed. Against that alien's fire breath, acid spit, claws and swords you're going to want to have a full-body suit of armor just like the ancient knights did as you incinerate the still-moving chunks of your opponent.
• INDEFINITE SURVIVAL: Your battlefield can't guarantee your soldier supplies. Your suit recycles CO2 into sugars, amino acids and oxygen. It's your food, clothing and shelter. Every bit of you is covered because every bit of anything that comes out of you is recovered. It's like a Fremen stilsuit and space suit hazmat suit and body armor all in one.
• SHRAPNEL: If your battlefield is full of high-explosive weapons blowing everything everywhere to tiny flying bits of shrapnel, the primary threat becomes either vaporizing (not much you can do about that) or getting hit with tiny projectiles that can cripple your soldiers. Without head-to-toe armor, no soldier will last more than a few minutes before they have so many minor wounds that they can no longer function. VR goggles tied to sensors let you see through the smoke, VR hearing means you aren't deafened by the blasts, respirators mean you can breathe when the air is full burning gasses. You can walk through the burning buildings, absorb some of the shockwaves from explosions, and so on.
• MEDICAL: Your suit is a walking medic. It detects injury anywhere on the body instantly, administering stabilizing chemicals and immobilizing crippled limbs. It tourniquets at the sight of bleeding, inactivates pain locally to allow a soldier to withdraw or keep fighting.
• ZOMBIE SOLDIERS: In the event your soldier dies or is crippled, the suit can activate the exo-suit and continue to operate. It will move the soldier to a medical facility or fire on opponents without the appropriate transponders. Dead soldiers can be 'ordered' into suicide attacks to draw enemy fire or carry bombs to destroy enemy positions. How terrifying is that?
• YOUR ARMY CONSISTS OF WEALTHY FOOLS: If your army is a group of poorly trained volunteers but supported by a nation of great wealth, then the sons and daughters of the elite are walking into a gunfight without the skills they need to live. Maybe your advanced society has forgotten how to fight wars as wars disappeared. Maybe it's a bushido thing where the elites lord it over the commoners but have an expectation that they be willing to fight and die for the nation. The solution? Those ridiculously expensive suits of armor that protect the fools from the consequences of their own actions. Once they figure out how to fight again, they're used to the $2.5 million dollar gear and don't know how to fight without it.

Answer 5

Homogeneity.

Who are the officers? Who is telling people what to do? Who are the high value targets?

If soldiers have their entire bodies concealed it is harder for an enemy to figure out which soldiers warrant more attention. Additionally, if you are a soldier, uniforms of this sort will conceal the fact that some of your fellow soldiers are aliens, or robots, or resurrected zomby soldiers.

Answer 6

You've already answered your question

The material the armor is made of is light and strong enough that it does not burden the solider much, or at most requires assistance in either a passive/very minor assistive exoskeleton to operate with

If the material is so light and unencumbering, then there would be little need to leave out armour pieces for weight or mobility. And so, given that an armoured bodypart is more resilient than an unarmoured part, it would be a no-brainer to cover up the entire body

Answer 7

Armor must be effective against the primary threat.

Platemail went away because it as guns become sufficiently advanced, they cease to offer sufficient benefit frequent enough for its cost and burden. That doesn't mean armor went away entirely, they just might not be in the form depicted in Star Wars. Kevlar vests, ballistic armor, etc. do exist and are frequently worn.

1) Material science advance sufficiently that body armor can sufficiently protect against the most common threat.

There can be multiple methods armor mitigates damage, and depending on your world the most common source of damage need not be kinetic in nature.

• Direct (As conventionally known)
• Ablative (Reduces or Eliminates the material from the incoming attack)
• Absorptive (The armor takes away the incoming attack from the weaerer, perhaps absorbing an electrical charge, or perhaps taking all the impact force in the wearer's stead)
• Dispersive (Maybe in your world bullets became obsolete and energy weapons became dominent, the armor disperses the energy harmlessly across its surface)
• Insular (Is the primary source of damage through biological/chemical warefare, or even electrical or heat?)

2) The environment or operational conditions warrants it.

Maybe your characters live on a hazardous planet. Maybe rockslides are common, toxic gas, heat waves, etc. Maybe they live under the sea. Armor isn't limited to combat use. Real-life Exoskeltons will probably see heavy duty use in the form of mining etc. before combat use, that doens't mean your soldiers cannot equip such an armor for non-combat purposes while on active duty. Once it is established that operational conditions warrants such an exosuit, they might start adapting it for combat utility based on field experience, but such a suit's priamry function will be to fulfill operation conditions.

Answer 8

Psychology + Uniform

Even light plastic armor with some kevlar under it goes a way to protect from discontent civilians. At least if the solders are in compact group. Also it improves their morale, as they see brave friendly solders around, even if they are scared inside. It protects from inconvenient scratches, or in case of falling from speeding motorcycle. Even if soldier is wounded, enemy cannot say how much or even wheter - so until really disabled every unit looks like fully functional.

Full body armor looks intimidating, may have demon-like face and does not show, if it contains scared newbie or hardened special unit veteran (but suggest the later). As such units are usually used against civilian "rebels" in big number, this looks make half their work done - week civilians take cover, run away scene and only "hardened criminals" are left to oppose such power demonstration.

Also having the same armor makes good uniform, to recognize your man from opposition fast. And small and cryptic distinctions make easy to be spotted by trained eye and recognize to fast evaluation of who is from which unit, which specialisation or which level of authority.

Plus it is easy to mass-produce such armors and have soon big army where only few are really trained, while it looks, like all are top specialist. Good for evel overlords as well for film studia :)

Answer 9

Armor Simply Needs to Become Lighter

Full body armor is always better than partial armor as long as it can meet the following two criteria:

• It must stop all common threats when hit.
• It must not be so cumbersome as to make one combat ineffective.

If you make your armor too thin trying to get full body coverage, it will not stop any common attacks; so, it is just waisted weight, but if you make it too thick or too heavy, then you can not move in it which also makes it useless.

The only reason we do not still use full body armor is that modern armor is not good enough to cover the whole body and stop a common riffle round without also being too heavy. To fully cover a solider today with riffle armor would mean loading him down with over 100kg of body armor; so, to compromise, we use armor that weighs just as much as a suit of medieval plate armor did, but we focus that armor only on the most critical and likely places to be shot. If you were to improve armor enough that you could stop most common riffle rounds with a full suit of armor that still weighs 25kg or less, then full body armor would very quickly come back into common usage.

Alternatively, if you were to improve a soldier's carry capacity to over 100kg using cybernetic or biological augmentation, then you might also see an increase in full body armor, but... this may be less likely since a higher carry capacity also means you can carry a bigger gun; so, higher caliber weapons may also become the norm simultaneously eliminating the advantages of more armor. So if you were to try to solve this problem with super strength instead of lighter armor, you need to make sure that the main threat will still be normal soldiers packing things in the 5.56-7.62mm range. So super solders have to be the exception, not the rule, for this solution to work.

Lastly, the problem we see a lot in sci-fi (and a lot of fantasy actually) is that common attacks go right through full body armor. When you look at something like a storm trooper, full body armor makes no since because every common hand gun seems able to go right through the armor and kill them, even when hit in the chest which should be the most armored part. However, if you instead envision something like the Kull from Stargate, you then have something that makes a lot of since to see full body armor on. Since their armor is actually effective at stopping most common weapons, they can walk right out into a hail of bullets taking shots to the arms, the legs, the face, the chest, and everywhere else. This means they can focus their whole effort on shooting the enemy and not have to waste any effort on not getting shot.

Answer 10

Secret police or collaborators from an occupied country.

Occupying another country is hard. Doing it with just my troops from home? Now that's tough. So I need some locals to help out, but the local population isn't on-board yet with my leadership and I don't want my people hassled when they're off the clock.

What better way to protect them than to conceal who they are with full body armour and face coverings?

Answer 11

Laser weapons

Their armour looks shiny..

Modern armour material can be reflective, that is why it may return.

In Star Wars, the stormtroopers have a light weight, reflective white armour.

Edit: In real life, strong laser beams will damage mirrors, same would happen to armor. A shiny armor would be most effective compared to clothes, when the angle of the laser light is not perpendicular to the surface. In any case, the comments below are justified.. body armor against laser should be thick and (very) heat resistant as well !

Answer 12

The armor incorporates a powered exoskeleton. It allows the soldier to carry the armor, and its power supply, without increasing their burden.

It will also allow the soldier to carry additional ammunition and supplies and even heavier weaponry. It could also include environmental protections (possibly including heating or cooling) that would not be practical for a soldier without such a suit to carry.

Answer 13

I'd say that the previous answers have covered most of the reasons why armor could return.

Effectiveness against commonly-used weapons

To add to the above, if the materials from which armor is made prove to be sufficiently effective against "short range" weapons (i.e., machine guns, pistols, shotguns, grenades) they would normally encounter during combat, then you'd have an argument for them to make a return.

Intuitively, as no sufficiently-light AND comfortable armor can protect from a hit to the face or hands, there is no reason to inconvenience soldiers with it, but if technology allowed for a face cover or "armor glove" that would save you from it, and be comfortable enough as stated in other answers, then military forces would definitely incorporate it.

Effectiveness against new weapon types

If the materials, alloys or fibres from which armor are made are better suited to stop or deflect new types of weapons (i.e., beam weapons), such as Star Wars' armor, which is supposedly "designed to disperse the energy of a blaster bolt and insulate the wearer, lessening injury", then full body armor would make sense.

This ties to the previous: if, for example, beam technology became cheaper, safer, more economically efficient or better overall, then militaries will switch to beam weapons and full body armor might be the most reasonable counter.

Answer 14

It's already returning. E.g. this is the Sotnik infantry armor that Russia is developing, planned to be done 2025(picked it as an example, because it looks the most sci-fi ish, there are plenty of others): https://taskandpurpose.com/military-tech/russia-sotnik-combat-armor-development/

You must remember, that body armor didn't go away due to ineffectiveness as such, e.g. 17th century plate was quite effective at stopping muskets from all but point blank range and would have been for a couple centuries more, until muskets went away, the word bullet-proof comes from the literal proof that it would stop a bullet that the purchaser required the armorer to provide in front of him:

However, due to the large quantities of high quality, tempered steel required to do it, it was too expensive to mass-equip the new armies of the modern age and due to the fact that no armor would do squat against cannon anyways, the cost-benefit equation worked out to: heaps of cheap unarmored troops > a small number of armored troops.

The tech for at least somewhat effective 3/4 armor has arguably existed since the 80s, but it was too expensive for the mass armies of the time.

Now, all militaries, including the Russian one are moving in the direction of a relatively small number of well-trained(hence valuable) troops, so the cost-benefit equation has shifted back to armor.

Answer 15

As you stated: the main reason that soldiers today only wear light partial armor is due to weight. The encumbrance of full-body armor outweighs the benefit of full protection.

To get back into full armor, one or both of that must change: either full body protection must become a definite benefit, or the weight of the suit must be reduced (or both).

One way to do this is with some variation of power armor. Things like exoskeletons that do exactly that are already in development. Such a suit will at least support its own weight, making encumbrance a net-0, and if it increases carrying capacity or walking speed, it gets to be a complete benefit.

This can be combined with benefits that other posters mentioned; like protection from environmental hazards (poison, or the vacuum of space)

Answer 16

The balance of Offence vs Defence swings the other way

Right now, the problem is that an armor that can stop a bullet in its tracks is expensive, heavy, inflexible and generally only good for one or two hits with low-calibre weapons.

Weapons technology has vastly outstripped personal body-armor to the point where we no longer defend against direct attack. Instead, we defend against secondary effects. Shrapnel, debris, glancing hits. Things that would cripple but usually not instantly kill.

This, incidentally is the ideal-case for a Storm-trooper's plasteel armor-plate.

Remember the prison-block in A New Hope? Remember how fast the fire-fight turned it into a storm of debris, shrapnel, smoke and alarms?

Those storm-troopers might die in a single direct-hit, but they shrugged off the shrapnel caused by blaster-fire hitting walls and blowing up nearby hardware like it was nothing. And they started shooting before the smoke from breaching the doors had cleared. Those helmets have all kinds of respirators, filters and optics to let them fight in hostile environments where a lesser-equipped person would be blind, choking and probably dead.

We also never see a clear over-penetration of the stormtrooper armor. Plenty of burn-marks and troopers falling over, but plenty of times a trooper was clearly still alive after being hit. For example one trooper fell off a catwalk when directly-hit and was clearly screaming as he fell.

One imagines that the storm-trooper armor is actually excellent as a defense against lighter blasters (such as their own E-11 carbines and hand-blasters) and most of the storm-troopers we see shot are actually alive, just knocked on their asses by the impact and burns they just received.

So back to the offence/defence tradeoff.

Stormtrooper armor is very light-weight. The clue is in the name "Plasteel", a lightweight polymer with properties reminiscent of steel.
If it weighs anything like say.. ABS, or a thermally resistant resin, it could be very lightweight indeed.
An armor that defends against most non-military small-arms well enough to prevent the trooper being killed in many/most cases, and can turn a military-grade glancing hit into something survivable, provides NBC protection, can see through smoke and gases, shrugs off shrapnel and acts as highly functional riot-gear?

Sounds great.

Now imagine what that would look like in real-world modern terms.

A suit of body-armor that can stop pistol-caliber hits entirely (even if the wearer gets knocked off their feet), and can turn a killing blow from larger caliber weapons up to .50 cal into something survivable.

We don't have the technology for that right now, but if we did, we might see the return of the suit of full body armor.

Answer 17

Your military strategy emphasizes sheer numbers and brute force over everything else. Remember that the Stormtrooper example is based on what is essentially a limitless clone army. Not all of them will require this level of full-body protection, but some will, and the full body armor is standard issue to all. It's the mass production of troops, without any exceptions or differences whatsoever, right down to every element of gear. Each branch of the U.S. military has its own standard working uniform, and each MOS has a relatively standard issue of gear all its own; for instance, a Bosun's Mate must be equipped with knife, lighter, and marlinspike at all times. This is just the same, except there's only one MOS throughout the entire force.

Answer 18

I recently read Seven Eves by Neal Stephenson. Potential spoiler:

Combat in that universe takes place mostly in space habitats. Conventional weapons are not ideal in that environment.

So they developed a kind of weapon that shoots tiny robots that avoid penetrating habitat structures. When landed on humans they would crawl around to find an opening in the suits and wreak havoc.

Full body armor could definitely be useful in this scenario to prevent or slow these small robots from entering their suits and bodies.

Answer 19

Armor doesn't have to stop incoming projectiles from infantry rifles (or bigger)

Up until very recently, there were no helmets that were rated to stop rifle rounds. They were meant to stop shrapnel and fragmentation. That's not to say that a rifle round wouldn't bounce off a steel helmet at the right angle. The same with early flack jackets. The amount of material required to make something bulletproof also made it impractical for infantry to run around with. After all, they are called $Flak$ jackets because they were issued to bomber crews to protect them from German Flak. It took another 20 years for infantry to be issued body armor.

Infantry kit is becoming heavier and heavier. According to this the fighting load of an infantryman in 1944 was about 75 pounds. The last time I went to the field, my load was 112 pounds. Eventually, the amount of kit an infantryman is required to carry will dictate that he needs some mechanical assistance. An exoskeleton will react A LOT poorer to a piece of shrapnel than the squishy thing wearing it. Think of the scene in Iron Man 2 with the prototype Iron Man suits from the other countries failing.

In short, the suit of armor would likely be designed to protect soldiers fully in the upper chest and head, with lesser protection to prevent unessasary mechanical injury everywhere else.

Answer 20

Let's make two changes:

First, a weapon already under development: Grenade launchers with rangefinders and spin-fused rounds. You take the range to whatever the enemy is hiding behind, you take the range to whatever's behind the enemy and set the grenade in between. The grenade launcher sets the fuse to a certain number of spins and you fire just to the side of whatever the enemy is behind. The grenade goes past and explodes beside your target.

Second, improved armor. Lightweight material that can repel grenade fragments.

Now, any soldier that doesn't have such armor is very vulnerable to such side-attack grenades. Note that you won't see many such grenades used because the armor stops them--so long as they are available it makes the enemy wear the armor.