Robert Barro, one of the country's top academic economists is interviewed about the Great Depression (hat tip Greg Mankiw.) Barro does a good job of discussing various factors of causation, and other factors of recovery, and offering a sense of relative magnitude. Political partisans tend to point to things that were bad or were good, but Barro explains what he thinks carries a low of weight. For those of you who want to see a chart of the Great Depression, here's one (but note that the y-axis does not start at zero).