<b>Every day, thousands of new secrets are created by the United States government. What is all this secrecy really for? And whom does it benefit?</b><br><br>Before World War II, transparent government was a proud tradition in the United States. In all but the most serious of circumstances, classification, covert operations, and spying were considered deeply un-American. But after the war, the power to decide what could be kept secret proved too tempting to give up. Since then, we have radically departed from that open tradition, allowing intelligence agencies, black sites, and classified laboratories to grow unchecked. Officials insist that only secrecy can keep us safe, but its true costs have gone unacknowledged for too long. <br><br>Using the latest techniques in data science, historian Matthew Connelly analyzes a vast trove of state secrets to unearth not only what the government really did not want us to know but also why they didn’t want us to know it. Culling this researc