Nick moulder is an assistant professor of history at cornell University. He's got a new book out, the economic weapon, the rise of sanctions as a tool of modern war. Nick says to understand how the us. Uses sanctions, we need to go back a century. It started happening about a hundred years ago. During and after the first world war. The nation lived over the brink into the boiling coldrun of war. And in order to stop countries from going to war, they needed something that was powerful, potentially as powerful as war itself but that wouldn't be war itself. That's kind of where sanctions come in.