I whole heartedly disagree with racial discrimination and white nationalism, but shutting down the conversation is a bad idea.  We want this in public so we can monitor their agenda and know who they are.  They also have a charter right to express there asinine point view and assemble.  Moves like this may further inflame the right and help in their recruiting.  Let them speak. Let them identify themselves. Let them wear their shame in public.  

"I disapprove of what you say, but I will defend to the death your right to say it"  -Evelyn Beatrice Hall