Why are they (USA Government) doing this to a fine Marine?

In your last sentence it says "Sgt Hutchins stated he did it for the USA..." Well that must mean he admitted to killing a civillian that was not a target so if that is so he should be tried, convicted and executed for murder (but I guess I'll have to settle for life). Where is it written into the laws that during wartime soldiers of any nation can kill civillians? Nowhere! Seems to me he isn't as "fine" a Marine as you think if he goes around killing civillians when he is not ordered to.