But you made the declaration in mid-day that Christmas was already over. However any terrorist action would have made the evening news, or been breaking news throughout the rest of the day and evening. So you were simply wrong when you made your post. Imbibing too much Christmas cheer, I suppose.
they also know they have to hit America by noon Eastern Standard Time to make the 5:00pm news cycle in the UK/Europe...
after that it's next days news and too late to spoil Christmas on Christmas day
by 3:00pm EST their window was well closed...