It is interesting that violence against newcomers is stereotypically a far right thing, but in SF it's the far left who are doing it.
http://nevertrustahippy.blogspot.co.uk/2014/01/believing-in-...
As Paul Evans says above
It's easy to cloak beliefs. Sloppy thinking results in dangerous allies. Simplifying to gain popularity can be disastrous. Scapegoating is always a mistake.