FOR AN INTERNATIONAL MOVEMENT supposedly fading into irrelevance, the gathering on New York’s Upper West Side on Saturday, January 13, was remarkable: an auditorium overflowing with hundreds of people arguing passionately about where Trotskyism is going and how to get there. On one side were the Spartacists and the International Communist League (ICL), whose U.S. outlet, Workers Vanguard, has long been known for its wit, high intellectual tone, and pugilistic style.