'How many terrorists are caught by security' is a question that is asked time and time again. Am I the only one that thinks this is a strange question which only shows frustration on our part? Do you ask your guard dog how many thieves it has mauled the past week? I don't know, maybe some of you guys do
Anyway, it's not only terrorists that are considered a threat. Think about the psychologically unstable people out there who can do just as much harm, think about deported aliens who might have a good reason to thwart their deportation, think about criminals, or chavs with knives on a long flight...