World politics and human nature are such that you can’t assume that virtue will triumph. Human beings are flawed, they make mistakes; some of them are deeply flawed and do things that are actually evil sometimes intentionally; therefore security is precarious.

Question: What forces have shaped humanity most?

Walt: Well again, if I had to push it to a single common feature, it’s when societies have been able to do sort of two things. One is generate a sufficient level of tolerance for diversity – sort of not insisting on a “one size fits all” approach to individual behavior, individual conduct, individual beliefs. And this, you know, comes out of, you know, the religious wars of the late Middle Ages where people began to realize that something had to be done to break the sort of cycle of recurring violence and develop a certain degree of tolerance. The second thing I think has been critical is encouraging the flowering of open thought and expression. I mean I’m a child of the enlightenment in that sense, that . . . that we don’t advance the human condition when we shut off inquiry; when we shut off discussion; when we shut off debate. So you know our capacity to live now is based in part on mastery of nature and scientific achievements. It’s based in part on understanding that for all of their flaws, markets turn out to work better than command economies. And then it’s by the way learning that markets can’t be allowed to operate purely on their own – that there has to be some political regulation to markets. It’s figuring out that democracy, for all of its flaws, turns out to work somewhat better than one person giving all the orders and expecting everyone else to carry it out. These are all cases where we’ve learned these things over time, over centuries. And getting the lesson right has often been quite a wrenching experience. But I think all of those things have contributed to greater mastery of the environment in which we live; which allows us to feed more people; which allows us to deal with disease; which allows us to build homes to then be able to keep them heated, etc., etc., etc. But . . . but at the same time, it’s also involved making some political developments and learning some political lessons as well.