I think you're over-estimating the quality of military firearms training and under-estimating how soldiers and marines are trained for war rather than policing.

I think you're over-estimating the quality of military firearms training and under-estimating how soldiers and marines are trained for war rather than policing. Friendly-fire military incidents are common; while it's associated with inexperienced troops, the reality is that experienced and "elite" troops still have many friendly-fire incidents. And then there are all the civilians that are killed as collateral damage.