what you are saying is lets not put in a proven, working system and subsidise GA.
max1, we already have a proven, working system.
You talk about the "very simple scenarios you offer up", so designing , testing and building GPS guided buzzbombs and keeping it secret can be whipped up in the backyard very simply.
The scenario 'starts' outside of Australia - that is, outside of our intelligence services 'comfort' zone.
... and I'm not talking WW3, just terrorism.