People over thousands of years were trying to reach harmony and peace in the world. As we can analyse there is no "perfect" world , but we can make it better.
First of all we can make world better by improving ourselves. We don't need to blame somebody or teach someone how to live , we just need to look after ourselves. Simply beeing polite to people will make our planet more peacful.
Government also responsible for nonviolent atmosphere.Equally important to resolve conflicts peacefully without involving military. To begin with countries should provide more diplomats in order to prevent wars.
As i have said there is no "perfect" world , but we can make it better simply being polite and peacful