This is an excerpt from the book First Platoon, by Annie Jacobsen, about the US Defense Department’s quest to build the most powerful biometrics database in the world: a system that can tag, track, and locate suspected terrorists in a war zone. But, as the world continues to battle a deadly pandemic, these big-data surveillance systems are playing an increasingly suspicious role in our daily lives. IN A STEEL container inside an American outpost in southern Afghanistan, an aerostat operator named Kevin was watching a man defecate in a farmer’s field. The man was wearing a purple hat. It was 2012, and Kevin was serving as mission director for the Persistent Ground Surveillance System team stationed here at Combat Outpost Siah Choy, located in the heart of volatile Zhari District. >"The company’s software can sift through enormous amounts of data, and those metrics can be used to make life-or-death decisions."