The causes of failure of cooperative societies are many. The most common cause is a lack of trust. We have lost trust in one another, and thus we have lost the ability to cooperate in any meaningful way. This is true for all cultures and especially true for those who have lived most of their lives in societies where there was little or no trust at all.
In most cases, the first thing people do when they are told they cannot trust each other is to start to distrust each other. People are naturally suspicious of others. They see the world as a complicated place that they don't understand, and so they look at others in their social circle or at work and judge them based on whether they seem trustworthy.
When you live in a society where people only trust certain groups of people, you become suspicious of other people as well. This results in the erosion of the basic social fabric of society. People start to believe that they are entitled to different treatment from the rest of us and that other people's behavior is somehow unjustified. Thus they become more suspicious of every person that comes into their social circle, and thus they become more distrustful of the entire world around them.
As they begin to distrust everyone else in the world, they become less capable of cooperating with each other in any meaningful way. The result is that they will try to protect themselves by withdrawing from the community in which they live, and they will start to do things differently from the way they did before they started to distrust the people around them. The result is that they will try to find reasons to blame others for their own mistakes, and they will do all kinds of strange things in order to justify their own behavior. And since their social circles are less diverse than before, they will do even more strange things, making it even more difficult to find people who can be trusted.
As this process continues, people will begin to withdraw even further from their own ways of thinking and will become increasingly closed-minded. They will start to limit their exposure to the rest of the world because their fear of other people is so great. And when they can't trust the other people who live in the same communities as they do, they will look down upon those who live in other places and cultures. and they will get into fights over nothing but trivial things.
It may take some time, but you will eventually win over the mutual trust. trust and understanding are very important if you want to continue to have a successful cooperative society. It may also help you win over a lot of people and build your own culture.