The one critical fact that the 'security industry' has never been able to answer is how employing some of the lowest intelligence and often criminally inclined people is genuinely going to improve 'security'.
The vast majority of it is to simply be seen to be doing something, the value of that something is generally highly questionable. Having worked in a risk management company I was appalled at the 'security advice' we received from our security colleagues. Anyone who can spell IQ can usually run rings around these people - it is cruel but very much like telling someone to pee in the corner of a barrel.....
But it is an industry that earns a lot of money and councils and bodies of that ilk - HIAL, BAA etc just love the whole 'jobsworth' mentality. If our wonderful 'govermint' really wanted to cut out waste it could all be removed in an instant with the instruction - if the guy next/nearest to you does something you do not like the look of - shout it out and if necessary clobber him/her. Goodbye a whole industry!