Why go airside?
Pauldyson,
To answer your question, it has already been done. If I remember correctly in Rome some years ago. I forget the group involved, but they ran amok shooting indiscriminately in the main hall. I cannot imagine the police being able to use their weapons in a crowded terminal for fear of hitting moving pax, so their hands are somewhat tied to respond.
As regards other contributions to this thread – Shamrock – we could all take banned items through, or at least try to. It is remarks like yours which encourage journos to try it on and then boast about it. IMHO, if that man was a real professional, he would do his deed and then go to the authorities to show the weaknesses in the system, not boast to the world how great he is. Thereby encouraging those who wish to cause harm to copycat his method. It could just be because of his kind I have greater restrictions placed on me when operating through AMS.