I’ve spent significant time in Africa. South Africa is higher than the US despite being a place where everyone has razor wire topped walls around their houses, and having the 5th highest murder rate in the world.

The US has problems. I myself was the victim of a violent robbery 15 years ago. But the idea that it’s less peaceful than South Africa, Lesotho, Sierra Leone, and only marginally more peaceful than Haiti? Come on…

The index is not just about "how peaceful is the average citizen's life", which is one part of it, but also includes other things like how many wars the country participates in, how much of their government budget goes to military, etc. You shouldn't get a good "Global Peace Index Score" while exporting violence across the globe.