Over the long-run, love trumps hate. For instance, Luz Long, a German athlete, gave Jesse Owens advice during the long jump. This came during the Holocaust, and he must have faced immense pressure not to help. Long won the silver medal, while Owens won the gold. Long was killed in WWII, but Owens befriended Long's son and served as the best man at his wedding.
Love is a much more powerful force than hate, but we have to choose it and decide to let it in. Hate and love cannot exist in the same place. As the Scripture says, "the greatest of these is love," and "love never fails." Even if you're not a Christian, you can believe these sentiments.
It is easy to point out acts of hatred in the world, but is just as easy to point to acts of love that have helped single individuals, families, and entire societies. We see more hate because it is pointed out to us, but maybe if we were shown more acts of love this would no longer be a question.
When human beings show love for others, this is a force for good. Hatred, however justified, can only bring about unhappiness. People who have suffered terribly at the hands of others typically find it easier to cope if they can forgive the perpetrator whereas those who hate, and commit hateful acts, often remain unhappy and bitter.