I guess I was confused about what it meant. I pretty much thought it was anything that pushed somebody's berserk button, whether that was due to past trauma or for another reason.

Mean this sincerely: thank you for explaining.

This isn't the case with me, but I actually can think of a way that somebody might end up with a trigger for execution scenes like this: if somebody close to them had been executed.

I wouldn't ever ask you or anybody else to pretend anything for my sake. But, similarly, it's not easy for me to pretend I'm okay with this, or even--to paraphrase a certain xkcd strip--say to myself "Okay, people are wrong on the internet, or I think they're wrong anyway, but I don't have to say so, I should just forget I ever read this and move on..."

At least I seem to have calmed down, and I'm ready to move on to other discussions.