I just came across an interesting article about a United States Peace Index, compiled by a progressive organization dedicated to documenting the levels of peacefulness in various nations of the world. Their formula for calculating a nation’s or state’s peace rating appears solid, though I haven’t studied it in detail. The ratings of various nations and states are also on track as far as I can tell.
The site is worth a look. We need to shine as much light as we can on what works and what doesn’t in promoting peace and what areas of the world need the most work in getting to a peaceful state.