Gentleman Aviator,
You make some good points sir, I believe no amount of security will prevent a well motivated terrorist force from at least trying to achieve it's objectives...
There is no doubt that security has to be increased to reduce the risk but ultimately every aircraft Commander should at least have a LAST LINE OF DEFENCE, whether firearms training or a non-lethal means of disabling assailants, In my own mind I believe a highly trained Sky Marshall (an archaic analogy perhaps but remember the shotgun riders on the old stagecoaches) is one of the most flexible ways to achieve some of the touted resolutions.
The most frightening aspect of this whole tragedy was it's devastating success, we have to give ourselves half a chance of making sure it never happens again........