It was late in the afternoon on August 20, 2013, another punishingly hot summer day in the small town of Stroud, Oklahoma. At 5:42pm, a train pulled into one of the town's industrial facilities, a receiving terminal for the Hawthorn oil pipeline. Nearby, a camera was watching.
The camera sent images of the 100-car train to the headquarters of Genscape, a Louisville-based company that publishes real-time data on physical energy flows. There, analysts monitored the train and watched as it discharg