Unfortunately it isn't many. The problem with the Mamdanis of the world is that they do not do education and their betrayals are of the marginalized. Their impact is to moderate and co-opt and undermine the left, not forward it. The idea that Mamdani should be criticized and rejected for being a cynical backstabber is completely at odds with the wider media narrative and his successful PR machine, the vast majority of people will know him as the smiley guy who does good things as a mayor. Likely many will choose Mamdani over basic principles and correct lines when they know basically nothing about either.
Our work is, as always, basically independent of what liberals and their opportunist loser promoters do. At most we can capitalize on rupture to do our own education events because they not only aren't inviting us (socialists, anarchists, etc - i.e. the left) to their events and work, they are picking fights and punching left as always and pretending that this is smart rather than reactionary.
