VS LHR is absolutely correct. For more information, see
this BBC link and other pages linked to from it.
'President Bush' (interesting choice of name!) is being deliberately provocative and is intending to scare those of you unsure of your position. While I'm in no position to give any reassurances on behalf of the Company, it is extremely unlikely that the Company would attempt any retaliatory action against striking CC after or during the event, with the possible exception of those who agitate
illegally against the Company or any individuals. All regular CC who simply follow a legal and mandated call for industrial action will be quite safe - though you will not be paid for any periods you are absent from work while striking (the Company has put out a clear guide to this). Your Union should give you the full guidance; I would be surprised if you haven't had it already - though, in this dispute, nothing your Union does (or doesn't do!) should surprise me!
If you are in any doubt, contact your Union directly. And don't take any notice of anonymous attempts at intimidation. It's ok to disagree, and it's ok to offer opinions and information, but intimidation is wrong. Ignore it.