ProfileGeorge Soros’s Right-Wing TwinMultibillionaire commodities king Bruce Kovner is the patron saint of the neoconservatives, the new Lincoln Center’s crucial Medici, owner of a vast Fifth Avenue mansion—and the most powerful New Yorker you’ve never heard of. By Philip Weiss (Photo credit: Courtesy of Bruce Kovner) After the opening-night performance of Tosca at the Met this spring, a handful of people found their way through a side door of the hall to the narrow corridor that leads backstage. One or two held flowers; a couple were in eveningwear. They were headed for the dressing rooms to congratulate soprano Maria...