"The thickness of your skin shall be seven spans - which is to say that you shall be proof against anger, offensive actions and criticism. Neither anger nor fury shall find lodgement in your mind and all your words and actions shall be marked with calm deliberation. Look and listen for the welfare of the whole people and have always in view not only the present but also the coming generations, even those whose faces are yet beneath the surface of the ground - the unborn of the future Nation."
quote from indigenous political constitution....in my article on how to heal divisions with political organisations and build some unity for change.
Violent disagreements within political organisations can derive from many sources - the myopia of leaders scared by immediate circumstances, ill-advised officials or the need to disrupt for the sheer chaotic joy of it are just some that come to mind.
Time after time the internal battle so aggressively fought one minute is easily forgotten the next.
Because change is difficult to achieve we can indulge in compensatory activity. Winning the ultimately minor internal battle can make us feel better about our inability to engage in more profound change externally.
Perhaps the most significant and worst motive for sectarianism is boundary maintenance. It is endemic on the left but of course also found in all kinds of organisations from Protestant churches to bowling clubs, yoga classes to origami networks.