Anger as a emotion can be understood better to handle it carefully. When we are unable to express our thoughts in a manner in which it gets transferred to another person we feel angry.
Firstly we need to understand that any Human being has the infinite power to decide what he will understand and believe in. As he becomes a teenager and am adult human being starts firming up on his beliefs. Once they are formed then only he can change them by understanding. No force in the world can do that. That is the power of the life atom or soul that energises the human physical body to make a complete Human being.
Once this knowledge or premise is accepted by us we can understand ourself as well as other Human beings better.
If we have some belief about what is just and fair and are not able to convey our thoughts to the other person we get angry. So does he and we are both in a spiral of anger and hatred.
If one of us is having a correct understanding of this situation then the change happens. Now instead of reflecting anger the person understands that the belief is different and change can not be forced.
Second point to understand is that every human being wants to be just fair and true. What is just and true is not clearly understood. That requires communication and exchange of information thoughts and logical reasoning.
Being patient till this exchange of information continues is a tall order. The person who understands that this is the only way and no force intimidation or torture can get the desired results will continue the exchange of thoughts and never get angry.
This is the reality. If people can start sharing these thoughts and agreeing to continue spreading these and more universal rules of existence hate can be quarantined and ulitamtwly done away from the social cloud of knowledge that exists. As new babies born do not get to see hate being practices they will never have that feeling.
This is a practical approach which can start with an individual and slowly spread.