A month ago, drones were spotted near Morris County, New Jersey. Since then, reports of further sightings in various locations in the region have been lodged on a daily basis, and anxieties about the origin and purpose of these unidentified flying objects have grown apace. “We have no evidence at this time that the reported drone sightings pose a national security or public safety threat or have a foreign nexus,” declared the FBI and the Department of Homeland Security in a joint statement. But...