Recent price history weakens an argument against easing US restriction of the export of crude oil.
The argument says exports above minor amounts now allowed would raise the benchmark US crude price.
Under current conditions, that's probably so. The domestic marker, West Texas Intermediate, is selling at a discount to its international counterpart, Brent Blend, with which it once traded at near equivalence. The WTI discount appeared in the first half of 2011 and has persisted except for a brief period in the middle of last year.
A reason for the discount is surging North American supply from tight oil plays and the Canadian oil sands. Surpluses have developed at key market centers—first at...