What do you mean?

On the way to drop my son off at a film shoot for a commercial this morning (ah, the joys of homeschooling!), he asked me if I thought the attacks in California yesterday were terrorism.  I told him that depends on what you mean by terrorism.  If you mean what I think alot of people mean by it (which is something close to brown people of a non-Christian religion killing white people), yes it looks like it could have been terrorism.  If you mean what the dictionary defines as terrorism (which is exactly the threat or use of violence for political objectives), then I’m not really sure.
Terrorism is a problem.  I know it may seem petty to make a prescriptivist vs. descriptivist argument when 14 people are dead and many more wounded (just yesterday).  But if we can’t agree on what words actually mean, then we can’t communicate.  Actaully it’s worse: we think we are communicating when we’re not.
Until we start using the word to mean the same thing (and applying it evenly in all cases where that meaning is warranted) no consensus will be formed and no corrective action will be taken that addresses the root cause, not just symptoms or specific incidences.  Let’s agree on what terrorism actually is, call all things that fit that description by that label.  Then we can decide what to do about it.