The Washington Post has retracted its story about Russian hackers penetrating the nation’s electricity grid with a virus found in a Burlington, Vt., electric company laptop. “Authorities say there is no indication of that so far [that Russians had penetrated the US electric grid],” according to an editor’s note attached to a corrected version of the story on the paper’s Web site. “The computer at Burlington Electric that was hacked was not attached to the grid,” the editor’s note read. News of the supposed hack had set off a firestorm of recriminations, with Vermont leaders calling Russian President Vladimir Putin...