A brief list of many of the laws of war, for purposes such as making the world's first Geneva-compliant colony or optimizing your colony for maximum war crimes.
Laws of War Guide
Keep in mind that the laws of war are really complicated, and this guide is probably not 100% accurate. Don't use this as a source on a history essay or as a pocket guide when you're drafted into WW2, or I will laugh at you when you get an awful grade/tried in the Hague. And of course, the UN is not going to send peacekeepers to your home for breaking the laws of war in Rimworld.
Legal and Illegal Weaponry
The general protocol for weapons is "Do not cause unnecessary suffering". Weapons that cripple someone without killing are almost always a war crime, and weapons that slowly kill and painfully kill an enemy combatant are generally going to find their way onto the same list.
- Chemical weapons are a war crime. These refer to gases that are poisonous or cause choking, as well as other weapons that use gases to kill. Mustard gas is an example. Crowd control gases such as tear gas are permitted, but only for domestic riot control.
In addition to being illegal to use, chemical weapons are also illegal to research, build, store, give, or sell to others.
- Biological weapons are a war crime. This refers to microorganisms being used as a weapon of war, such as giving people blankets infected with smallpox or flinging plague victims into a city. They do not have to target humans, and weapons targeting animals or plants still qualify as biological weapons.
Like chemical weapons, they also cannot legally be researched, built, stored, given, or sold to others.
- A weapon with non-metal fragments is a war crime. This means things such as plastic bullets or grenades which fire non-metal shrapnel. This is because there is no way to find the fragments easily, which causes unreasonable suffering to soldiers they are used against.
- Anti-personnel land mines are a war crime... unless you're the United States, Russia, China, India, or one of 28 other UN member states. This was prohibited by the Ottawa Treaty, and Wikipedia has a nice little map on which countries did or did not sign this. That being said, those which did not sign often have other restrictions on what does or doesn't go.
An anti-personnel land mine is one which is designed to kill people rather than vehicles.
- Incendiary weapons are a war crime... if there might be civilians in the area. An incendiary weapon is a thing which is primarily designed to start fires. An example of this is a flamethrower or white phosphorous.
If the weapon is napalm, it comes with the additional restriction of only being okay if the enemy is using plant cover to stay hidden.
- Cluster munitions are a war crime. If it releases a large number of fragments for injuring people in a wide area, it's illegal. This is because they are rather good at killing innocent civilians and filling an area with unexploded ordnance, or UXOs.
- Laser weapons are illegal... if they are used to blind people. This refers to laser weapons which are solely used to blind a combatant rather than kill them. If the laser weapon is mainly meant for murder but also sometimes causes blindness to its target in its attempts to kill them, it is perfectly legal.
Prisoners of War
A Prisoner of War is a captured lawful combatant. Lawful combatants are members of one of the two warring armed forces, and excludes medics and chaplains. They are legally allowed to fight in a war, and are entitled to become a POW if they surrender.
- A full list of what is or is not a lawful combatant is on this wikipedia page.
The following treatment of POWs is required:
- The POWs must be treated in a humane fashion. They must be respected as human beings.
- They must be given the opportunity to inform their families and the International Committee of the Red Cross (ICRC) of their capture.
- They must be allowed to communicate with their relatives and within reason receive packages from them.
- They must be given a sufficient amount of food, water, housing, and medical care. Your 1x2 rooms and raw meat aren't going to cut it, here.
- They must be paid for any work that they do, and that work cannot be degrading or dangerous. They cannot be forced to work on anything related to the war.
- They must be released shortly after the conflict ends.
- They do not need to give any information outside of their name, age, and rank, and should not be compelled to do so.
Of course, these only apply to a legal combatant. While an illegal combatant is still to be given them until given a fair trial, afterwards they are subject to the enemy nation's full justice system.
Other Parts of the Laws of War
- Harm caused to civilians has to be proportional to the military gain of the operation or tactics harming them. Bombing a city to cripple industrial capabilities and destroy military bases within is acceptable, bombing a city as a fun afternoon activity or to get that blood lust mood bonus isn't.
- In order to be a lawful combatant, soldiers must follow certain criteria. This includes having a uniform, being recognizable at a distance as being a combatant, and not committing war crimes.
- Combatants need a commanding officer, unless the conflict was so sudden that one could not be chosen beforehand. This officer can be held accountable for any war crimes committed under their command.
- It is illegal to shoot at people or vehicles flying a white flag, as it shows a desire to surrender or communicate with the enemy. As with the protected symbols, the wearer is required to act neutrally while wearing or displaying a white flag.
- If a person is protected from the laws of war (such as a doctor or civilian), using them as a human shield or camouflage is a war crime.
- It is illegal to attack doctors, hospital ships, or ambulances bearing several protected symbols.
- The Red Cross
- The Red Crescent
- The Red Crystal (either with or without a Star of David in the centre)
It is required to be neutral while wearing or displaying any of these, and committing acts of war while doing so is itself a war crime and allows the wearer/displayer to be freely shot at.