i think we're entering a period when it's less obvious to other governments that the u.s. is in less of a position to play a deterring role. that doesn't raise the risk of someone saying, let's start a nuclear war. i think that's highly unlikely. it's what we learn from this story of human cultural evolution. while we can't wish war out of existence like the song suggests, we are looking to respond to changes in the environment, and that's what really makes large-scale wars a bad, bad thing for everybody. >> thank goodness we can end on an optimistic note. pleasure to have you here. >> thank you. whatnext up, what's wrong w western politics? my friend has a diagnosis and a prescription. we'll be back in a moment.