I'm not surprised either.
Pop a round through some Muslim bomber, who's just blown your mate's legs off, scrote's head in the Iraqi or Afghan desert & come home to a few years in jail.
You are absolutely right.
If you are on active service the option should be open to put down an enemy or perceived one in any way and not have the worry about being Court Martialled for it.
Grief, the training is second to none and the fact of putting someone down comes as natural as writing a letter home. It's the job. That is why the British Army in the past was so feared by the rest of the world - you just don't take prisoners and you certainly don't wait to see if you get shot first before taking action (as happened in N Ireland)
Silly as it may be, but when on a 'war games' footing, you were told that anything you did in contravention to the civilian/criminal law had no place.
You would be answerable to the military.
I remember once on my first 'weekend warrior' adventure sat in the cab of a Bedford personnel carrier asking if I had to adhere to red traffic lights, infact anything of a driving nature. The Sgt. told me to 'put my F****** foot down and don't stop for no one.
Brilliant I would have lost my licence with the antics I did on my way to Aldershot that night if I had have been in my car! Red light - what red light - used to feel sorry for my mate stood up in the cab with his head out of the cab roof hanging on to his Brengun for grim death.