Quite simply they are taken over by the collective mindset of us against them.

I grew up in Northern Ireland at the peak of The Troubles there and witnessed mob mentality firsthand. Seemingly normal and even placid people can be swept away by a mob mentality if they do not have a heightened sense of awareness or complete Presence. Respectable members of society will turn into barbaric animals when caught up in that energy with no thought or care to who is being hurt and killed...even innocent children.

What happens is that both sides become so identified with their own story or cause and they cannot see beyond that narrow perspective or that another side to the story may exist. They believe that they are right and the other is wrong and become so entrenched in that mindset that they will do anything to defend it.I think on some level the others are no longer perceived as human beings and the mob becomes totally insensitive to and incapable of seeing or feeling the pain of the others...it is quite horrific to watch. I think normal perceptions become completely distorted and each side believes that they are the victim and the other is the perpetrator and even the original cause that began the fight becomes secondary to the need to win and kill the enemy.

I think mob mentality is a classic example of the collective ego in action. Both sides believe that they possess the truth, when in fact they are the ones being possessed by a dysfunctional mindset.

However as Fairy Princess pointed out the opposite happens when a group of awakened individuals get together, and that's where we need to put our attention :)

I think it is harmonic resonance. The energy from each person is amplified when it reaches a like vibration. An individual can get themselves all worked out if they let their mind control them instead of controlling their thoughts. If one person can do this alone, then when their vibrations meet and amplify with all the other people's negative energies, it just keeps amplifying until the energy subsides, changes, somebody gets shot, etc...

This is why I asked the question about making the movie Hysteria, about the effects of this mass hysteria and how it affects everything from other people to the environment. If we could make a movie and show people the affects of the hysteria and then a version of what it would be like if we controlled our thoughts and kept from the hysteria, and it could show how to accomplish this.

The same, but opposite happens when good energy amplifies, like in a good worship service.

Edit 8/11/11-

I was thinking about this question and how I left out the part about mob control shooting people, and how the surprise or shock changes the vibration. I was then thinking about a song, then I put the two together and had a funny idea. So, what if during a mob riot, somebody starting blasting some fun music and then started a group dance on a stage where all could see? The thought makes me smile and laugh. I could just see all the people in the mob riot, one by one pause, listen, turn toward the music, see the dancing and totally change their vibration and maybe even join in in dancing. Then you have a flash dance! Haha

I loved the posts FP and Michaela wrote and I agree with both. Additionally, when I went to Germany as an exchange student (a long time ago in 1977) I had the privaledge of speaking with many WWII survivors. Many were still alive at that time and were still working as pastors, teachers, and so forth and I met them in the course of my daily life there. People explained being "overpowered" by the group mentality to the point of no longer thinking for themselves, while Hitler was in power and particularly in his presence when the mobs would be nearly entranced. Many realized that a mysterious force had them under sway. There is no other way to explain how ordinary, good people were so overcome by evil. And Hitler's people knew a lot about using lighting, words, colors, music and more to influence people as much as possible.

Many years ago I listened to an interview with an old man who had attended one of Hitler's mass speeches. I don't recall the details, that is whether he was forced by his employer to go (which was not uncommon, by the way) or whether there was a different reason. Anyway, this man opposed Hitler (again, I don't remember how active he was in the German Resistance, but many who were never mentioned in history books did what they could to stop Hitler and his friends, and to help those suffering and in danger).

At the beginning of the event, in a large arena, he looked at the masses around him, trying to figure out what made adult, thinking, intelligent people not only follow Hitler but completely succumb to him.

The show began, went on...

... and suddenly the man found himself standing on top of his seat, clapping, shouting encouragements along with the rest of the audience...

What I do remember is the shame in his voice as he talked - more than thirty years later - about this having happened to him.