“Crack spreads — energy industry measures of the gap between crude prices and refined products like diesel — have soared in recent days as the global fuel picture is increasingly determined by global politics and war,” Axios reports.“Crack spreads are basically the profit margin that refiners add on top of the price of a barrel of crude in order to come up with the prices they charge for refined products like diesel.”Financial Times: Iran war windfall puts Big Oil on collision course with Trump.