A tanker of oil from Texas set sail for South Korea late Wednesday night, the first unrestricted sale of unrefined American oil since the 1970s. How that $40 million shipment avoided the nearly four-decade ban on exporting U.S. crude is a tale involving two determined energy companies, loophole-seeking lawyers, and an unprecedented boom in American drilling that could create a glut of ultralight oil. The Singapore-flagged BW Zambesi is the first of many ships likely to carry U.S. oil abroad under a new interpretation of the federal law that bars most sales of American oil overseas. Analysts say future exports appear wide open: as much as 800,000 barrels a day come from just one of the many U.S. oil fields pumping light oil. Though U.S. policy on oil exports hasn’t changed, production of this kind of oil, known as condensate, is surging. This early shipment “is the wedge that’s […]