It ain't all that damn hard furious.
scenario:
your under orders to clean out a town.. you round up the townsfolk and line em up. they are unarmed. an officer tells to to lock and load.
no problem here, is there?
Your unit, while advancing has captured a significant number of opfor prisoners. they are disarmed. your officer says lock and load.
no problem, right?
A train pulls into the sation. offloading commences, the prisoners are herded into a building with ovens. they are to be executed.
no problem, right?
Thers no doubt.. not one little bit of doubt that the orders are unlawful. the REAL dillema is: what do you do about it?
THATS the hard part. Not deciding what an unlawful order is.. but what you, Private Joe Blow; can do about it, right there and then.