There's a difference between violence and needless violence, too – I'm a pretty violent person, in that I am capable of sustained acts of extreme violence, and such acts don't bother me. On the other hand, I don't go seeking out opportunities for violence, and generally either it's in the ring or it's in defense of someone else.
So, professionally or beating-up-bad-guys, I guess. :D
But don't worry! I'm not going to judge you for wanting to be capable of physical defense, and I'm not going to ask what you want to do with it, unless you want to train for something specific. Does that clarify anything?