Robert Barro of Harvard University and Stanford University's Hoover Institution talks about disasters--significant national and international catastrophes such as the Great Depression, war, and the flu epidemic in the early part of the 20th century. What do we know about these disasters? What is the likelihood of a catastrophic financial crisis in the United States? How serious is the current economic situation in the United States? The conversation also includes discussions of economic stimulus, tax policy, and the recent worldwide rise in commodity prices.