is an act of violence designed to cause fear in a society or particular group - lynching blacks was an act of terrorism in my view. Violence in war generally is not terrorism, since the goal is forcing compliance of a group rather than making the group afraid - but sometimes it probably is terrorism.
Its true, as soon as you try to assign motive to an act of violence, it gets more difficult to define. revenge vs self defense, hate crimes, insanity, etc. is all really murky and difficult to know for sure.
The other part of terrorism is that it has to be intended that lots of people see the violence so they are scared and appalled - so the media is complicit in making an event terrorism.
So the Boston Marathon is terrorism, while some of the horrible Home invasion/multiple execution crimes are not.
Anyway, the one thing I would add to your list of wrong doing, is that it is difficult to tell if #1 is wrongdoing or incompetence. The government seems pretty incompetent. Incompetence is probably the most common and the least evil of the explanations.
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