Neither violence nor non-violence are always the answer. Anger is sometimes necessary, as is killing people. At the same time, violence is often counter-productive. It can solve physical problems of physical or other aggression, but it does not lead to inner peace. Only tranquility can do that.
As I look at the world, it seems to me that only a fool would be immune from worry. How can anyone not see that bad things happen to everyone all the time, often with little warning? Always, as Christ said, “wars and rumors of wars”, which can be seen as a metaphor for all the things we worry about: business downturns, making mistakes at work or home, inflation/deflation, recessions, Global Warming/Global Warming conspiracies, serial killers, car accidents, diseases, UFO’s, what people really think about us, what sort of season our sports team/hero will have/is having, terrorism, gray goo, the rise of robots, etc.
The complexity of our world differs greatly, of course, from 1,000 years ago; but for all that, they no doubt worried, too. And they objectively had, daily, much more substantive challenges than face us. Weather and disease were much greater enemies. People got sick and died–children, frequently–for reasons beyond their ability to explain. They lived for long years with painful ailments that could today be treated.
How can a rational mind conquer worry? Worry serves a purpose: it provides the energy to plan for multiple contingencies.
The answer of course, fiendishly simple, is acceptance. We must accept that change, pain, and death are inevitable. But how do we do that?
As I see it, some sort of spiritual faith is invaluable in this, in that you can bridge the gap between this world–full of unavoidable sorrow–and one in which our cares are gone. You have to live in two worlds, and occupy two selves–your Earth self and your spiritual self. To the extent that you can bring the light of heaven to Earth, you can live in peace here.
This is what I see. I have not figured out for myself how to do it yet, but I have some leads. I will post any successes.