The walking dead TV series got me thinking about zombies and really how much of a threat they would be in a real situation. Logically zombies are only dangerous to unaware populations that do not know their weakness. They are slow moving, most asthma sufferer can outrun one, they are unable to use tool so a locked sturdy door can keep them at bay for a while, they seems to have human level senses so they need to see, hear or smell you to find you, they are stupid as shit, the average zombie can be tricked to fall from a building top by someone on another building and finally they are very fragile.
Now the last one might surprise a lot of you as zombies are often characterized as almost unstoppable with unending endurance. While it is true that zombies seems to be able to survive trauma that would disable or kill an average human being, they like the previously mentioned human being are very susceptible to head trauma. In fact, jugging by the mythos on the subject zombies seems to be destroyable by any damage to the brain. Now most authors require the trauma to be in the form of a bullet or force sufficient to pierce the skull, but one has to wonder why. If these impacts were sufficient to destroy the brainpower required for a zombie any similar head trauma would cause similar result.
That is where the zombie loose some if not most of their threat. While a group of survivor probably does not have access to high end military hardware, in the unstoppable tide of undead stage of the collapse (before the world become an apocalyptic wasteland) the armies of the world are still sufficiently organize to deploy as a response to the threat and use modern high explosive and powerful weaponry. Now, World War Z would have you believe the undead masses would simply shrug off high explosive as they don’t need most of their body function to survive, but that is forgetting that explosive force created a great deal of head trauma, and as we’ve seen zombies are pretty bad with that. Not to mention that unlike living human, they do not have any protection reflexes, which mean they will not protect their head from debris increasing the likelihood of fatal head trauma.
Finally, there is a “final” nail in the zombie’s coffin (too many pun on that line right?). Information, 20 years ago almost no one had any idea what to do in case of a strange outbreak of reanimating corpse. Today, well even non geek know that in case of reanimating corpse outbreak you should 1) avoid contact and bites, 2) aim for the head and 3) double tap, always double tap. Imagine how well the zombie apocalypse will go for the zombies when everyone and their dogs know how to efficiently kill them.