One of the favourite topics on this forum is zombie outbreaks. What would you do in a zombie outbreak, where would you hide, what game hero would deal most efficiently with a zombie outbreak etc.
The only common assumption in these lines of thought is that the rest of society will go to hell, and that you will have to start civilization over again. This is a faulty assumption if the zombie outbreak were a classical one.
First, what do I mean by classical zombies? By classical zombies I mean zombies that are dead humans devoid of thought, who walks slowly and attempts to bite the other person, frequently devouring them. A bite from these will sooner or later transform you into a zombie (if not eaten). They can safely ignore lost limbs, holes in their body etc, their only real physical weakness is their head: Destroy it somehow(through decapitation or a headshot for example) and you will destroy the zombie.
There are differing theories as to how long it will take from a classical zombie bites its victim until the victim is transformed. Max Brooks claims that it will take as much as 24 hours until the transformation is complete.
If this is the truth the zombie infestation will never reach critical mass. Imagine a lone zombie in Los Angeles: After it has bitten a few people a proper law enforcement agency will intervene and put it in a straitjacket, or street justice will destroy it(people will defend themselves and kill or restrain it). Say it bit 10 people this way. It is hard to imagine it biting more people: After all, it is not very fast, and people tend to avoid maniacs they have seen biting other people. After 24 hours, those 10 become zombies, and they bite 10 more. After 24 additional hours those 10 has become 100; by this time law enforcement and doctors have discovered the strange condition those people are in. If the police has detained but one zombie, a doctor should immediately recognize that damn, that guy's heart doesn't beat!
After 72 hours, we now have 1000 zombies. But now people are alerted to the threat, and Los Angeles is evacuated, all evacuees are placed in isolation tightly monitored by medical personnel. The army is set in against the threat, and the zombies are quickly destroyed by sheer numbers. When further details about the zombies are discovered, they find that destroying the head of all dead people will stop any eventual zombie infestation. Yes, it is that easy: According to Brooks, victims bitten by a zombie spend a couple of hours dead before they rise as a zombie again. During this time, their head can obviously be destroyed, thus ending any possibility that they become zombies. While zombie scenarios usually contain some kind of ethical dilemma along the lines of: "Is it moral to kill him because he might become a zombie and endanger us all?", this doesn't: Since the viction spends a few hours as a dead man before rising, all we have to do is to destroy the brains of the already dead.
If there are more than one zombie the numbers change, but not the logic; the spread will still be too slow for the zombies to reach critical mass. 24 hour intervals are quite simply too long.
Let us assume, then, that the time needed to become a zombie is smaller, just a couple of minutes or less. In such a case, numbers could quickly overwhelm a major population centre. But would it destroy civilization as we know it? Most certainly not.
As mentioned, zombies move at walking speeds. This is 6 km/hour if you walk fast. While zombies have the capability to walk fast when they are "excited", they usually don't. A normal speed of 3 km/hour is not unreasonable to assume. Since zombies also tend to wander aimlessly, this walking speed is perhaps overestimating their capability to move over long distances.
So let us say that Los Angeles has turned undead. The undeads spread in all direction at speed of 3km*24hours=72 km/day. In one day they devour or convert the cities in the vicinity. After 24 hours people will certainly have gotten to know, either by word of mouth or by mass media, that they have to flee the area. And flee they will. By now the army is alerted. The army will move in and crush all zombies.
Many people would think this is an arrogant assumption because OMG! Teh zombies only die when they aer shot in the head!! But guess what, tens if not hundreds of thousands of people fighting the zombies will find out fairly soon methinks. It's fairly intuitive really, and seeing as the zombies march towards the soldiers at walking speeds the soldiers will get plenty of time to aim.
Once the surprise element is taken away, killing zombies would be like shooting fish in a barrel. As long as your escape route is clear, soldiers can simply walk away when the zombies are too close. Nowadays creating clothes covering your entire body that are capable of withstanding a bite should be the easiest thing in the world; in fact I am 100% certain that it already exists. Also, a sniper barricaded in a tower with a few days worth of supplies would be able to entirely destroy hundreds of zombies a day, and zombies would be unable to do anything back. An armored vehicle could easily be outfitted in such a fashion that humans would be unable to break in using raw force. If the zombies came in a large horde, heavy machine guns and explosives would decimate them so fast that it wouldn't even be funny. No zombie would be able to destroy a tank.
On the civilian front, it would take little effort to make a city impervious to zombie attack. Just make it mandatory for every home owner to have a safe floor where it it impossible for a zombie to break in. Also make it mandatory to have a couple of days of supplies stored. This is a relatively easy feat to achieve for most families: Just cover your windows with something and make the door more solid. If you have a second story, make the stairs retractable or something. If you live in an apartment building it is even easier, since those are usually made out of cement or bricks or something solid anyways; these people only need to have solid doors. If every mans house is a fortress, people can run home at the event of an outbreak, and those unlucky few who have become zombies will wander in the streets as target practice. Also note that this doesn't necessarily have to be government decreed: People will likely try to make their family as safe as possible even if the government doesn't make it mandatory to do so.
So in conclusion, a classical zombie infestation can be a veritable local threat, but on the national or international level it will be rather harmless.
The only common assumption in these lines of thought is that the rest of society will go to hell, and that you will have to start civilization over again. This is a faulty assumption if the zombie outbreak were a classical one.
First, what do I mean by classical zombies? By classical zombies I mean zombies that are dead humans devoid of thought, who walks slowly and attempts to bite the other person, frequently devouring them. A bite from these will sooner or later transform you into a zombie (if not eaten). They can safely ignore lost limbs, holes in their body etc, their only real physical weakness is their head: Destroy it somehow(through decapitation or a headshot for example) and you will destroy the zombie.
There are differing theories as to how long it will take from a classical zombie bites its victim until the victim is transformed. Max Brooks claims that it will take as much as 24 hours until the transformation is complete.
If this is the truth the zombie infestation will never reach critical mass. Imagine a lone zombie in Los Angeles: After it has bitten a few people a proper law enforcement agency will intervene and put it in a straitjacket, or street justice will destroy it(people will defend themselves and kill or restrain it). Say it bit 10 people this way. It is hard to imagine it biting more people: After all, it is not very fast, and people tend to avoid maniacs they have seen biting other people. After 24 hours, those 10 become zombies, and they bite 10 more. After 24 additional hours those 10 has become 100; by this time law enforcement and doctors have discovered the strange condition those people are in. If the police has detained but one zombie, a doctor should immediately recognize that damn, that guy's heart doesn't beat!
After 72 hours, we now have 1000 zombies. But now people are alerted to the threat, and Los Angeles is evacuated, all evacuees are placed in isolation tightly monitored by medical personnel. The army is set in against the threat, and the zombies are quickly destroyed by sheer numbers. When further details about the zombies are discovered, they find that destroying the head of all dead people will stop any eventual zombie infestation. Yes, it is that easy: According to Brooks, victims bitten by a zombie spend a couple of hours dead before they rise as a zombie again. During this time, their head can obviously be destroyed, thus ending any possibility that they become zombies. While zombie scenarios usually contain some kind of ethical dilemma along the lines of: "Is it moral to kill him because he might become a zombie and endanger us all?", this doesn't: Since the viction spends a few hours as a dead man before rising, all we have to do is to destroy the brains of the already dead.
If there are more than one zombie the numbers change, but not the logic; the spread will still be too slow for the zombies to reach critical mass. 24 hour intervals are quite simply too long.
Let us assume, then, that the time needed to become a zombie is smaller, just a couple of minutes or less. In such a case, numbers could quickly overwhelm a major population centre. But would it destroy civilization as we know it? Most certainly not.
As mentioned, zombies move at walking speeds. This is 6 km/hour if you walk fast. While zombies have the capability to walk fast when they are "excited", they usually don't. A normal speed of 3 km/hour is not unreasonable to assume. Since zombies also tend to wander aimlessly, this walking speed is perhaps overestimating their capability to move over long distances.
So let us say that Los Angeles has turned undead. The undeads spread in all direction at speed of 3km*24hours=72 km/day. In one day they devour or convert the cities in the vicinity. After 24 hours people will certainly have gotten to know, either by word of mouth or by mass media, that they have to flee the area. And flee they will. By now the army is alerted. The army will move in and crush all zombies.
Many people would think this is an arrogant assumption because OMG! Teh zombies only die when they aer shot in the head!! But guess what, tens if not hundreds of thousands of people fighting the zombies will find out fairly soon methinks. It's fairly intuitive really, and seeing as the zombies march towards the soldiers at walking speeds the soldiers will get plenty of time to aim.
Once the surprise element is taken away, killing zombies would be like shooting fish in a barrel. As long as your escape route is clear, soldiers can simply walk away when the zombies are too close. Nowadays creating clothes covering your entire body that are capable of withstanding a bite should be the easiest thing in the world; in fact I am 100% certain that it already exists. Also, a sniper barricaded in a tower with a few days worth of supplies would be able to entirely destroy hundreds of zombies a day, and zombies would be unable to do anything back. An armored vehicle could easily be outfitted in such a fashion that humans would be unable to break in using raw force. If the zombies came in a large horde, heavy machine guns and explosives would decimate them so fast that it wouldn't even be funny. No zombie would be able to destroy a tank.
On the civilian front, it would take little effort to make a city impervious to zombie attack. Just make it mandatory for every home owner to have a safe floor where it it impossible for a zombie to break in. Also make it mandatory to have a couple of days of supplies stored. This is a relatively easy feat to achieve for most families: Just cover your windows with something and make the door more solid. If you have a second story, make the stairs retractable or something. If you live in an apartment building it is even easier, since those are usually made out of cement or bricks or something solid anyways; these people only need to have solid doors. If every mans house is a fortress, people can run home at the event of an outbreak, and those unlucky few who have become zombies will wander in the streets as target practice. Also note that this doesn't necessarily have to be government decreed: People will likely try to make their family as safe as possible even if the government doesn't make it mandatory to do so.
So in conclusion, a classical zombie infestation can be a veritable local threat, but on the national or international level it will be rather harmless.
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