Peace is a simple allowance of loss.
Once violence of any kind (property, physical, psychological) has happened, the damage is done. No amount of fist-shaking, hooting and hollering, anger or revenge can undo what's been done. So not to accept what has happened is simply irrational. The world you wish for -- the one before the violence happened -- is gone! We can't get it back. Struggling to try and get it back is delusion and will lead to more suffering.
Once we allow the loss to sink in, we can calmly take stock of our surroundings, and determine the best course of action for our new future; a future which, again, can never be a repeat of the past. Yogi Bhajan quote: "When you don't live by yesterday, then you start to live for tomorrow." That's because it doesn't make sense to do anything else.
I say the best course of action on purpose. Ultimately, it's not our feelings or thoughts that determine outcomes, but the actions we take. Cry out loud, express your feelings, do whatever it takes to accept the present; then take action towards the future you want. Nothing else makes sense.
There is a funny kind of excuse that goes around where people say that their intention is what matters. Even though you do something that is self-defeating or harmful to your goals, you reassure yourself by reiterating your intention. Intentions are important because they guide thinking and eventually action. But to ignore actions and their results and to focus only on intentions is delusion.
There is a confusion rampant in the world about the nature of peace and generosity, namely, the idea that we must be selfless to achieve good works and lasting peace. In fact, to be effective agents of change we must be totally selfish. We begin by asking "what do I really want for myself?" For many of us, peace and freedom, for ourselves, is high on the list. When we look into how we might achieve for ourselves what we desire, we begin to understand generosity as a cause of our desired end-effect. Another way of saying this is that our interests are interconnected with the interests of other living creatures. The person who is selfishly trying to achieve his desires is a stronger agent than the one who acts for some external reason.
If I choose to exact revenge, who am I hurting? When I steal from my friend, do I gain? Thinking about questions like this brings us closer to peace.
When somebody asked the Dalai Lama: what can we do about monks in Burma being subjected to great suffering? The Dalai Lama thought for a bit and then answered "I don't know." I wanted to jump out of my seat because the answer is so obvious: "Work on yourself!" Cultivating peace within yourself is more powerful than guns and politics.
Many of us want change. We realize that our present way of life is unsustainable. And yet, we have a silly idea that we can get change through some disconnected political way, and avoid having to change ourselves! If we can just elect the right leader, and come up with the right thinky-think solution to this and that detail, we'll be on the right track towards peace!
There are a couple of problems with this. The first is that we are all interconnected, and so any change to our external society will require changes of us. We can let go, so that we can proactively participate in what we will become; or, we can stoically stand in one place, refusing to change, as a once-suppressed tidal wave of revolution crashes down upon our heads.
Another problem with external solutions is that without inner peace, you can't experience peace. So as soon as you get what you want out of this political situation or that, your inner tension dictates that you look for another distraction, or even create a problem where none existed, so that you can try to resolve it! Our own inner conflict and struggle will probably eventually manifest itself in the outer world. How can we be agents of change in the world when our insides are all conflicted with self-denials?
Most people don't realize that changing the world necessarily implies changes within. Your life will not be the same in a peaceful world. So we must be open to a new life. In fact we might as well start building it now, because it goes both ways-- changes within necessarily imply changing the world. Ghandi: "Be the change you want to see in the world."