Peace in the world depends on peace in the hearts of individuals; this depends on each of us practising ethics by disciplining our negative thoughts and emotions, and developing basic spiritual qualities.
When we are young and again when we are old, we depend heavily on the affection of others. Between these stages we usually feel that we can do everything without help from others and that other people's affection is simply not important. But at this stage I think it is very important to keep deep human affection.
The antidote to hatred in the heart, the source of violence, is tolerance. Tolerance is an important virtue of bodhisattvas [enlightened heroes and heroines] - it enables you to refrain from reacting angrily to the harm inflicted on you by others. You could call this practice "inner disarmament," in that a well-developed tolerance makes you free from the compulsion to counterattack. For the same reason, we also call tolerance the "best armor," since it protects you from being conquered by hatred itself.
Sometimes religion becomes yet another source for more division and even open conflict. Because of that situation, I feel the different religious traditions have a great responsibility to provide peace of mind and a sense of brotherhood and sisterhood among humanity.
If one's cause is supported by sound reasoning, there is no point in using violence. It is those who have no motive other than selfish desire and who cannot achieve their goal through logical reasoning who rely on force.