We desire peace. But peace is a goal, not a policy. Lasting peace is what we hope for at the end of our journey. It doesn't describe the steps we must take nor the paths we should follow to reach that goal.
The Buddha said, 'Nothing can survive without food. ' This is a very simple and very deep truth. Love and hate are both living phenomena. If we do not nourish our love, it will die and may turn into hate. If we want love to last, we have to nurture it and give it food every day. Hate is the same; if we don't feed it, it cannot survive.