Intra-alliance fighting has always been a concern because of Greece and Turkey. Article 5 is probably the only reason they haven't already gone to war. But yeah the US would fight all of European NATO that answers the call, win a pyrrhic victory, and destabilize Europe for the next 100 years.
Nyoka
I know they specifically mentioned temperament in the selection section of one of the sniper manuals. Not sure about special operations.
Honestly, most special operations selection processes seem to have very little to do with the actual what most Tier 1 units actually do. CAG, for example, has a 40 mile solo nav course as part of their selection.
Yeah, they are sort of just the worst in JSOC (although one wonders about the CIA direct action groups). But between this shit, the Nazis in the KSK, and Australian helicopter musical-chairs, it really does seem like there's something about special operations that attracts the worst a country has to offer.
There's mixed evidence of whether or not mass shootings have a contagion effect, that people who are already "primed" see this shit on tv and decide that today's the day.
Or it could just be chance.
But maybe, here's an idea, we don't let people who make terroristic threats have guns. I don't care about what kind of gun, if you credibly threaten to murder a bunch of people, no gun for you.
This is the way.