 You have been listening to Morning Edition from NPR News. For many stations, we will bring you back to your regularly scheduled programming after a short break. We are going to continue our coverage later throughout the day. You can head to NPR.org for the latest at any time. And, of course, much more on all things considered later this afternoon. My thanks to my colleagues, Carrie Johnson, Domenico Montanaro, and Ron Elleving, and our guest, Professor Rick Hassan. I'm Michelle Martin, and this is NPR News.