All because of a bureaucratic white paper process by learned academics, advised by "Expert" Civilian members of the ADF given to an elected government who hasn't got an idea of what is wheat or chaff. Nothing has changed, we have learnt nothing from history. Build a line in the sand. Every line ever built was defeated by mobility and controling the theatre of operation.
Terrorist theatre of operation is urban and individual. Assimilate with your target then strike at your own choosing. No standing army can protect us from that.