Does a person have to be important before they are considered assassinated instead of just plain murdered?
Nope. You don't have to be 'special' if you are assassinated. It just seems like they only use that term for Celebrities, President, etc. That's so prejudiced. I'm jealous. But assassinated means to be murdered unexpectedly, or for impersonal reasons.
in my opinion, assassination implies a motive designed to make a point, rather than a personal reason against the victim.
Assasination is when someone gets someone else to kill another someone else. Murder is generaly solo.