like Mr lambert says, living with it would be the hardest part.
to kill for no reason would be hardest. to kill a person i hate (there are quite a few.) would be a piece of cake.
soldier on soldier would be a kill of kill situation.....
Yes as long as it was something I believed in or the person had done somthing terrible or hurt my family or were a danger to me personally. Otherwise I'm very anti-violence.
Of course I would kill if I had to ~ it probably goes without saying that if a family member (or yourself) was in danger you wouldn't have to think about it.
Before I had kids I thought I couldn't kill anything, and that I would rather starve than kill a rabbit, for instance. It's all different now. I would offer my own life in order to save my childrens or husbands lives.
Desperate times call for desperate measures, depends on the situation really. I've never thought about it. Nobody really knows what they are capable of unless you they're actually put in such a position where their life is in danger and killing your opponent is the only option. In which case, I'd say most people (if not all) would use their natural "fight" mechanism to survive, its pure instinct.