I'm pretty sure "our own army" WILL shoot 'civilians' here in this country, if it comes to it.
It's a highly complex thinking path to get to which civilians, and if non uniform young men are even civilians at all, etc.
I know the army has been training for homeland contact for a few years, since they cleared out mock-up Afghan villages and built mock-up Brit council estate style training ranges, but I have no idea yet what "civilian" might really mean in that context. It could be us or could be embedded and or sleeper cells from other countries.