My family has been solidly military since the Spanish-American war. All the men have been military, all the women have married military. I spent 26 years in the Air Force myself.
If you recall back when there was debate about the CIA engaging in torture, the real issue was whether the CIA (which had actually never officially done interrogations before) should be required to adhere to the US Army interrogation field manual--which excluded torture as an interrogation tool.
If you noticed, it was the generals who spoke most strongly against torture. The generals do not want permission to torture. Permission given to torture in extreme situations would become a mandated requirement, because war is always an extreme situation.
The Law of Armed Conflict (the Geneva Conventions applied to military regulation) is mandatory annual training for every person in the US military. Each person is given a general course and then we are all given a second course in how the LOAC applies to their specific military specialty. Many people are given additional courses on the LOAC that are even more specific to particular job assignments. When I was involved in nuclear targeting, I was given more courses in placing Desired Grounds Zero according to even weather patterns to achieve the necessary destruction of military targets with the least civilian casualties.
All of this is not a matter of being soft on the enemy. It's a matter of reminding ourselves that even as men of war there is a floor of barbarity below which we will not descend.
No commander wants to lead a mob of barbarians. And if you think about it, you would not want such men who believed no level of indecency or violence was immoral to come home, marry your daughter, and buy the house next door.
"We never went that low" is something a soldier should be able to say to himself when he comes back from war and return to civil society. "My men never sank that low" is something a commander should be able to say to himself when he comes back from war and returns to civil society.
Even if a circumstantial exigency forces a soldier to do something he would not have otherwise done, at least he can say, "That is something I would never have otherwise done." In the dark hours of the night when he's 80 years old and has nothing to do but think of his past, at least he can say that.
The men who cannot say that are the men who can never return to being a farmer or shopkeeper or student. They become the fighters in ISIS who don't have a home to go to, who couldn't go back home if they had, but can do nothing but find new wars to fight.
The Law of Armed Conflict is not for the sake of the enemy, it's for the sake of ourselves. And nobody seems to know that more acutely than the men who have stood on that precipice.
The chickenhawks sure don't get it.