It’s not about outright war crimes, these SAS troopers ambushed a group of IRA operatives coming back from attacking an RUC station with heavy machine gun and AK74s and was ambushed by the SAS on the way back.
“was not planned and controlled in such a way as to minimise to the greatest extent possible the need for recourse to lethal force”.
Can you imagine rules like this being applied in a war zone? The IRA fancied themselves as soldiers fighting on the battlefield. In a war you destroy the enemy when the opportunity presents itself, you don’t mess about trying to arrest them when they are an armed threat.
Remember Idiot-in-Chief Obama's "rules of engagement?"
It was accurately assesed: "... true war-by-wonk, in which a deadly brew of lawyers, politicians, soldiers, and social scientists endeavors to fine-tune the use of military force...."
I think there’s going to be a change soon. And the “rules” of such things are about to scrapped completely. They’ve already been shredded pretty thoroughly.