Today on The Gist, we observe the 100th anniversary of the start of World War I with a feature about the start of World War II. Mike asks Ron Rosenbaum, author of Explaining Hitler: The Search for the Origins of His Evil, about how a genocidal monster is formed, and whether the Holocaust would have happened without him. For the Spiel, all you missed on ABC’s This Week. Get The Gist by email as soon as it’s available: slate.com/GistEmail Subscribe to the podcast in iTunes: itunes.apple.com/us/podcast/slate…id873667927?mt=2