Terrorism threat is not so much about what actually happens , but rather about what might have happened, or what might happen in the future. Just look at the latest incidents. What actually happened was an unsuccessful attempt to commit a crime. In the meantime, crimes on much bigger scale are actually being committed around the world. What we are scared of now is what might be coming next. And that, in its turn, depends very much on the spectacularisation of the "event" through the media, by politicians, etc.
As explained by Derrida, terrorism is not about "what is presently happening or what has happened in the past but the precursory signs of what threatens to happen. It is the future that determines the unappropriability of the event, not the present or the past. Or at least, if it is the present or the past, it is only insofar as it bears on its body the terrible sign of what might or perhaps will take place, which will be worse than anything that has ever taken place."
Will we allow the traumatic experience to carry away our common sense, or will we try to cope with it using patience and rationality? The choice is still ours. Personally, I am more worried about possible luggage overweight than terrorism when taking a flight next week.