For a big part, they didn't. Of course in smaller circles people knew exactly what happened, but nationally it was denied or downplayed and covered up by the South. Until sometimes they couldn't. Like in the Emmett Till case, who was on a family visit from Chicago and was lynched in Alabama. This got a lot of media coverage nation wide for a change.
Usually yes, and I will acknowledge that skipping this step is showing laziness or incompetence, but I don't think children are already reasonable, especially when they're tired (this happened late in the evening) and already committed to throwing a tantrum. And in this case the whole situation might have been already stressful for the parents anyway, which doesn't help. Probably they should have talked about it more way before they entered the plane, and prepared the kid for what was going to happen. And maybe they did. But the situation then being what it is I think options can be very limited, and there probably wasn't much time to try reasoning with the kid
Sure, we know what not to do, but do we also know what we should do instead then? Sometimes you need kids to comply within a certain time frame and that's going to require some pressure one way or the other and no, it's not going to scar them for life
The meaning is clear, but I never heard "it's curtains" irl. It seems it was popular in gangster movies mid 20th century and apparently (still?) well understood in the eighties, but are people in the US still saying that?
Maybe check out Fragile (by Sting) and it's background story
I read his books in German, but there seem to be English translations and unless they're really bad it should not matter for enjoying his writing or the stories. I read Noah first, but as far as I remember it's a very good thriller, but not that psychological, at least in comparison. After that I just started his books chronologically. Does not matter though, there is no continuing story line or returning characters. But I can vouch for the psychological character of at least his first four books (Therapy, Amok, The Child, and The Soul Breaker).
I you like psychological horror/thrillers then Sebastian Fitzek will keep you busy (and maybe awake at night)