This question is at the very heart of our overstretched expeditionary adventures.
Combat is an inherently risky activity!
In Korea, the UK lost over 1100 military personnel in 3 years. No Coroners inquests, no Health & Safety prosecutions, no calls for ac grounding etc. We are all proud and thankful for their sacrifice.
War involves painful sacrifices which is part of the risk we understand. I do not believe that anyone goes to work in the morning with a deliberate aim of killing their comrades.
It seems to me that the Coroners want a 'risk-free' combat operations. The whole point of war is that people get killed and we should think long and hard about commiting to such action .... that's the point!