… is from pages 250-251 of the collection of previously unpublished (or only obscurely or inaccessibly published) essays by Milton Friedman, The Indispensable Milton Friedman  (Lanny Ebenstein, ed. 2012); specifically, it’s from the October 2000 interview with Friedman done by the producers of The Commanding Heights :
INTERVIEWER: Do you think the Chile affair damaged your reputation, or more importantly, made it harder for you to get your ideas across?
MILTON FRIEDMAN: That’s a very hard thing to say, because I think it had effects in both directions. It got a lot of publicity. It made a lot of people familiar with the views who would not otherwise have been. On the other hand, in terms of the political side of it, as you realize, most of the intellectual community, the intellectual elite, as it were, were on the side of Allende, not on the side of Pinochet. And so in a sense they regarded me as a traitor for having been willing to talk in Chile. I must say, it’s such a wonderful example of a double standard, because I had spent time in Yugoslavia, which was a communist country. I later gave a series of lectures in China. When I came back from communist China, I wrote a letter to the Stanford Daily newspaper in which I said, “It’s curious. I gave exactly the same lectures in China that I gave in Chile. I have had many demonstrations against me for what I said in Chile. Nobody has made any objections to what I said in China. How come?”