They weren’t elite anything mate they were ordinary soldiers on the ground in the middle of what was effectively a war zone. I don’t know enough about the back story to comment but I can hazard a guess they didn’t need to be there and that would be the fault of the operations commander of the day. Soldiers just don’t open up on inoccent civilians if that was the case the troubles in Ireland would have been over in a month. Something triggered that shooting and somebody would have given those soldiers the orders to carry on firing. You cannot blame the troops on the ground who in reality are on