Dark Transits are a Stopgap not a Solution

Washington has accomplished an important feat by stealthily moving oil through the Persian Gulf despite Iran’s proclaimed closure. But the means it has relied on can’t become normal maritime behavior.Treasury Secretary Scott Bessent said on August 27 that the United States had facilitated the movement of 130 million barrels of oil through the Strait of Hormuz in the preceding two weeks. That amounts to over 9 million barrels per day (bpd), roughly half of pre-war exports through the chokepoint.Most of these vessels make “dark transits,” when ships sail with their automatic identification system (AIS) turned off. A ship’s AIS transponder broadcasts its location, course, speed, and other data via dedicated maritime radio frequencies to nearby ships, shore-based AIS receivers, and low-earth satellites, which convey that data globally. Dark transits are typically used by sanctioned vessels or ships moving illicit cargo because standard maritime trade, under normal conditions, doesn’t derive benefit from sailing without AIS. But licit maritime trade has increasingly been forced to move through the Middle East waterways on dark trips to avoid attack.Kpler data identified more than 1,500 ...