South Korean refiners have reduced jet fuel shipments to the U.S. and redirected supplies to Japan, where they can sell at higher prices given current market conditions tied to the Iran war. This matters because the U.S. relies significantly on Korean jet fuel imports — if the redirection continues, it could tighten domestic fuel supplies and push prices higher. The broader context is that the Iran conflict is disrupting global energy flows and forcing countries to recalculate supply chains based on risk and profit margins rather than traditional trading relationships.