She’s the power behind the red curtain. Zohran Mamdani’s secretive, newly named chief of staff, Elle Bisgaard-Church, is a Democratic Socialists of America true believer who convinced the far-left group to back him for mayor and helped craft his “Department of Community Safety,” insiders said. The two 34-year-olds forged similar paths to the heights of New York City political power — cutting their teeth in antiwar and pro-Palestinian college campus activism and toiling in lefty nonprofits before making the leap into state government. “Few have played a more central role in this movement, or in every victory we have achieved...