The Evolution of Trust

In The Evolution of Trust, Nicky Case uses game theory to help explain our epidemic of distrust.

Meanwhile: it’s 2017, the West has been at peace for decades, and
wow, we suck at trust. Surveys show that, over the past forty years, fewer and fewer people say they trust each other. So here’s our puzzle: 

Why, even in peacetime, do friends become enemies?
And why, even in wartime, do enemies become friends?

This has been around for a while (maybe since 2017 or so?) and I think about it every few years, then I struggle to locate it, so here it is for the next time I remember I forgot about it.