A month and a half into the war between Iran and the US and Israel, Michelle Wiese Bockmann has seen one constant: disappearing ships. This is not unusual in the Strait of Hormuz, says Bockmann, a senior maritime intelligence analyst at Windward AI who has been tracking shipping across the globe for 30 years. For nearly a decade now, “shadow fleets” engaged in shady practices—say, violating international sanctions by transporting crude oil from Iran—have periodically turned off their transponders. These devices typically broadcast ships’ names, locations, routes, and IMO (International Maritime Organization) numbers. Those unique, seven-digit IMO identifiers allow trackers like Bockmann to trace the ships throughout their floating lifetimes. Jamming and “spoofing” these transponder signals, either by interfering with their satellite signals or creating false ones to make the ships appear where or what they’re not, isn’t new. But the scale is.…