Ive met lots of terrible little dogs and most of the time the owners are obviously to blame. Laughing about their dog's behaviour not telling it off because 'aww hes only little' etc..
Two Chi's I knew who were great little dogs were two who were almost always off lead and played with other dogs in the park they were athletic strong little dogs not primped pampered playthings.

99% of the time when a dog is badly behaved look to the owner , because its a case of human error.

Well, there's two sides to everything, and Chis, along with many toy dogs, seem to be born into a universe with an extra dimension so they can have even more.

First up is bad owners-- and into this category I lump owners who are not necessarily bad, just bad at being dog owners. These are people with little or no experience with dogs and no experience with training. Little dogs are chosen by people who don't know what they're doing because they're cute, and little, and there's this added notion-- who knows where that comes from-- that they will therefore be no trouble at all, little more than a Tamagotchi with legs. Easy to care for, no fuss, no muss, certainly not a heap of trouble like some big rancid Labrador who's just going to eat and fart and take up all your time walking. What gets lost is that these are DOGS. Little, sure, and limited because of their size, but 100% dogs.

Not only that, but Chihuahuas are one of the little dogs who are generally very high energy and very highly social. They need activity, they crave interaction, and they're going to get it one way or another. They make great companions for active people, for kids, for people who want a doggy sort of dog in their lives but have little space (they are popular in urban Japan, for example, where living and walking space is at a premium, but with time you can make a lot with what you've got). They make terrible companions for elderly people of more feeble dispositions, for people with limited time to give them, or people who really just want a cuddly toy, but unfortunately this is just the demographic that they attract, to everyone's detriment.

Then there are the breeders. Because temperament is often de-emphasised with little dogs, there are those who pay little attention to it and happily choose pretty dogs who have dainty feet and fit inside a half size teapot but who happen to be neurotic as all get out over a less attractive but solid, even, good-natured dog. Cute sells. If as much attention were paid to temperament in the breeding of little dogs as it is in, say, Collies or Airedales or Newfies, we might see a very different picture.

But that guy in the video... that guy was clearly doing everything to wind up the dog that he could. He was tormenting that dog, plain and simple. Yeah, I'd call a behaviourist, but not for the dog. I'm amazed the little dog was so restrained.

Sorry, didn't mean to offend anyone. I was referring to the video and the way the owner was treating the dog.....and I still think poor dog and idiot owner!

20 out of all the Chi's in the world? that's a lot isn't it !

We have some lovely ones here, but then there owners aren't dickheads .

Do the dogs know this? Do they have any comprehension or ability to understand this or how to be grateful.

I love my dogs and I understand them and their various problems, they bring me joy and contentment but I don't force them to be petted if they are not in the mood for it.

Because defence is the best form of attack and many terrier breeds do this. It can be very effective .

Often a dog will show body language that shows the dog is tressed eg a tongue flick or give conscious warnings like trying to move away or growling . Most people don't recognise the stress signs and ignore the growling and snapping because they think they shouuld be able to do what they like to a dog .

Dogs that bite without warning or "unprovoked " have probably been punished for growling so go straight to bite , are in pain or they may have another physical problem such as a small brain tumour or epilepsy.

There are very few videos of dogs just being dogs put out on the net. 'here's my dog and I'm stroking him' wouldn't get many hits. 'Here's my dog, look how the little beggar reacts when I pester him' gets loads of hits.

Sad, but true

There is bad genetics and breeding in Pit Bulls too. Back to Chihuahua, even with the nice owners it makes sense when you do consider the bad genes. It isn't really a fault of the dog, but the person who irresponsibly bred them.
I have a couple who don't like their nails cut but they won't snarl or bite. So I know what you mean. However imagine tormenting them all the time. All dogs probably have a limit. If you thought it was funny to make your dog uncomfortable, then if she finally growled you kept doing it? Then you'd be creating a pattern for the dog, when you touch or even reach for her feet she might growl.
Small dogs also can't always get away as easy. So they might snap in defense.
I don't think a dog choosing fight over flight makes them extremely mean. In my case don't think any of the Doxies Ive seen have ran either. They have been aggressors too. Not provoked or defensive biting.
I agree about people and their stupid videos. It is never funny. It's not fun but stressful for the dog. If it were a big dog people probably wouldn't find it cute or funny.

Good God, talk about generalizing a whole breed!!