It may seem unrealistic to think we can ever become free from hatred, but Buddhists have systematic methods for gradually developing a tolerance powerful enough to give such freedom.
Human beings are not intrinsically selfish, which isolates us from others. We are essentially social animals who depend on others to meet our needs. We achieve happiness, prosperity and progress through social interaction. Therefore, having a kind and helpful attitude contributes to our own and others' happiness.
There is no denying that consideration of others is worthwhile and that our happiness is inextricably bound up with the happiness of others. There is no denying that if society suffers, we ourselves suffer, and the more our hearts and minds are afflicted with ill-will, the more miserable we become. We can reject religion, ideology, received wisdom, but we cannot escape the need for love and compassion.
If you have fear of some pain or suffering, you should examine whether there is anything you can do about it. If you can, there is no need to worry about it; if you cannot do anything, then there is also no need to worry.
If we ourselves remain angry and then sing world peace, it has little meaning. First, our individual self must learn peace.
This we can practice. Then we can teach the rest of the world.