Wow, are US vets that tweaked? I mean, just say a bad thing about them and they will kill you, with out remorse? Blimey, sounds a bit worrying to me. You make them sound like a bunch of well armed psychos living on a hair trigger. Such people roam free in the US? Sounds terrifying.
Or are you doing them a bit of a disservice there?
That's a terrible cop-out argument. If they're actually skilled - say so. If the bulk of the workforce isn't? Then saying so only hurts fixing the problem.
If they're so unstable that being told they're not good at their job sends them in to a killing rage, they shouldn't have that job.