The surge in the political power of the Democratic Socialists of America (DSA) is real. That much, everyone agrees on. Reactions to this reality, though, cover the full spectrum. “About time,” say veteran leftists, for whom the current moment feels like the culmination of decades of hard organizing. “Change is possible!” say bright-eyed young people being rescued from disillusionment by socialist New York City Mayor Zohran Mamdani’s charm. “What the hell is this?” say members of the Democratic establishment, caught by surprise due to their habit of never speaking to normal people, if they can help it. “The communist threat is back,” say Republicans.

And unions? Well. Unions are interesting. With a handful of notable exceptions, it’s fair to say that unions in the United States haven’t decided what to think yet about the recent rise of DSA and their aligned candidates. This points to one of organized labor’s sticky flaws — but more important, it points to an enormous opportunity that smart unions should be salivating over.

New York, where Mamdani’s victory in the mayor’s race last year kicked off DSA’s ballooning national profile in earnest, is a useful preview of where this is all going. When Mamdani first entered the Democratic primary, he was considered a fringe candidate. Scandal-ridden former Governor Andrew Cuomo was considered the safe, establishment choice. Even as Mamdani rose in the polls in the months leading up to Election Day, he only attracted endorsements from a small number of local unions, like United Auto Workers (UAW) Region 9A, whose leaders had preexisting ties with the Left. The city’s biggest and most powerful unions almost all either endorsed Cuomo (1199SEIU, 32BJ SEIU, the Hotel and Gaming Trades Council, and more) or, like the United Federation of Teachers, endorsed no one at all in the primary, unable to bring themselves to go on record for a self-declared socialist even as his chances began to look more plausible.