I Was There For DSA’s Radicalization. The Democrats Are Next.

Jonathan Chait's worry piece is worth reading, but the more interesting document here is written by someone who was actually inside DSA and watched it happen. That's a different kind of warning than the usual "moderate Democrats fret about optics" column. This is someone saying: I watched this organization go from a fringe debating society to a machine that just won real elections in the largest city in the country, and I know exactly how the takeover works, because I lived it.

The pattern is not complicated. A small, disciplined, ideologically committed group shows up to the meetings nobody else wants to attend, does the unglamorous organizing work, and slowly owns the institution while everyone else is busy having day jobs and normal lives. Democrats have spent a decade treating DSA like a noisy but harmless younger sibling. New York just found out what happens when the younger sibling gets the keys to the car.

What should worry the Democratic establishment isn't that DSA has ideas outside the mainstream. It's that the party's usual antibodies, donor pressure, primary muscle, message discipline, don't seem to be working anymore in the places DSA has targeted. Institutions don't get radicalized by one dramatic vote. They get radicalized by attrition, meeting after meeting, until the people who used to show up stop showing up and the people who never left are running the show.

We've been saying for years that the Democratic coalition was papering over a real fight between its liberal establishment and its socialist activist wing. New York didn't settle that fight. It just showed which side currently has better attendance.