The buzzword in Democratic politics this week is “civil war.”New York City Mayor Zohran Mamdani helped fuel it by taking a real political risk: He endorsed Darializa Avila Chevalier, Claire Valdez and Brad Lander in competitive House primaries, backing insurgent progressives against two incumbents and a candidate favored by the party establishment.Join now to continue reading.Members get exclusive analysis, bonus features and no advertising. Learn more.If you’re already a member, sign in to your account.