There are lots of definitions of terrorism but none of them are "accepted". Every definition is disputed by somebody. That is the reason many news agencies don't label any attacks as terrorist attacks and nor should we. Investigating and adjudicating as to whether a particular incident falls within the US State Department definition of terrorism (for instance) when the State Department itself has not given it's opinion on the subject is most definitely Original research. Remember that an argument can be made that the Boston Tea party could qualify as a terrorist incident under some definitions. That is why I am suggesting we list all notable violent incidents and ongoing conflicts and let our readers decide whether they want to call a particular incident terrorism. This would let us include the 2011 Tucson shooting for instance without having to determine the shooters motive. We could also include incidents like the 2010 Kingston unrest even though that was criminal, rather than political, violence.