Do you feel that, every time a soldier kills its totally okay and in no way at all murder? I would say that yes - there have been many times when a soldier is a paid murderer. But sometimes no, they are not.
Surely a lot of this has to do with the choice to kill or not to kill. Killing in self defence, or to defend another I would say is not murder.... because there is no real choice.
If there truely are other options other than to kill a person, and the choice that is chosen is to kill, well that is murder really.
Then you're contradicting yourself, since there are always other options than to kill a person, including in the examples you said weren't murder. You can choose to surrender. You can choose to die. You can choose to let other people die. There's always a choice. What you're doing is what most people do - call it murder if you disagree with the choice and not murder if you agree with the choice. Different people draw the line in different places, but they're using "I agree/disagree with the choice to kill" to define whether a killing is murder or not.
Also, the person I was replying to defined murder as planned killing, so they were including all war and all defence in which killing is intended.
I honestly believe that capital punishment does more harm than good in the long run, it does not deter crime if anything it makes it worse because crims then act as if they have nothing to lose and either behave smarter or wilder because of that.
I think the same thing. The saying "may as well hang for a sheep as for a lamb" is an old one for a very good reason. Besides, most criminals don't make their plans on the basis of being caught. Some do, but most don't. They either don't think at all or they expect to not get caught. A perceived increase in the chance of getting caught is a far better deterrent.