Look up Nazi Germany for one example. Look up the Crusades for another. Thousands of people dead because their leaders threatened American economic expansion. The possiblility of excess is just far too great. The least force required must be applied.
Many causes are work being harmed and causing harm.
Police officers are still heroes in my book. Justice was alien to him. Causing harm in a just cause must be left to those who know where and when harm is appropreate. Hubbard therefore disqualified himself. The Church of Scientology therefore disqualifies itself.