This last year I have been quite a Steven pinker fan. The is in my opinion one of the great minds alive today.
https://www.youtube.com/watch?v=R-28etfOLUw
Steven Pinker is certainly not a libertarian and he did convince me with his book "the better angels of our nature" that human beings does need a leviathan to keep the peace given the nature of our social structures. I just don't see the state as an efficient way of doing it, for obvious reasons.
Either way, in this video he makes a good case for what libertarians have been saying for awhile. Essentially we are richer than we have every been, violence is on decline, trade is up etc.