Where's the line? Do I have to kill you in person to be on the right side of it? What if I use a gun instead of a knife? Is that still okay? How about if I

Where's the line? Do I have to kill you in person to be on the right side of it? What if I use a gun instead of a knife? Is that still okay? How about if I have all kinds of armor and a bunch of buddies behind me, and I blow you up with a grenade, how about then?