On its surface, Andy Greenburg’s new book, Tracers in the Dark: The Global Hunt for the Crime Lords of Cryptocurrency, is a standard crime story. Fans of true crime podcasts will enjoy the crypto version and get a seat in the Federal Bureau of Investigation van as United States federal agents track down criminals through their crypto transactions. The first story recounted is that of a crooked Drug Enforcement Agency agent who stole funds from the online drug market Silk Road. It also addresses the hunt for Dread Pirate Roberts, aka Ross Ulbricht — Silk Road’s founder. Ross’ operational security was pretty good. He used Tor for everything. He used an encrypted laptop that locked itself when it was closed. He didn’t share personal details. But in privacy, all it takes is one mistake. He was...