It struck me as something that could be particularly clever. It is clearly a threat, and most likely a bluff. But should it be brought to court, they could cla

It struck me as something that could be particularly clever. It is clearly a threat, and most likely a bluff. But should it be brought to court, they could claim it was indeed internal communication (and that you should feel bad for reading it in the first place). There may even be an internal response saying "no you can't be put on the no-fly list", which isn't forwarded to you of course, to keep up with the masquerade.