The Asic card does that. If someone is noticed wandering around a light airctraft doing a preflight or putting packages into it, the Asic card immediately identifies the person has been checked out by Federal police rather than having to detain the person for hours getting checks made.
There are current threats, why would we do a Neville Chamberlain?
That's your asessment, but how about this: "..... also known as ......returned from .......late last month and is again extolling the virtues of jihad at the ......... Islamic Information Centre in ................
The location is an innocemt looking suburb in Melbourne with dozens of restaurants, mostly Chinese, Laotian amd Vietnamese.
or
And when they are caught by Fed police: ".........who is serving 15 years jail for planning a terrorist attack in Melbourne."
Or the graduate of the learning centre who lured Vic Police to a site and opened fire on them, luckily being shot dead by Police.
There's been a steady stream of potential terrorists around Australia for decades.
They've done that overseas, using shoulder-fire missiles, but they can do that from outside the perimeter of the airport.
The ASIC process does protect us in lone wolf attacks. Overseas , where ones and twos of terrorist showed up at training airfields and asked for training and no questions were asked even when they said they didn't need to do landings. They were given training no questions asked, they learned how the aircraft could be accessed (the no keys, she's OK, Let's Go! method) they loaded their aircraft and they attacked their targets. .
In those cases the instructors either echoed the sentiments we're reading,where people don't think a terrorist would ever come to their airport, or that arabic people saying they didn't need to be taught to land were just a bit of fun or whatever lame excuse they came up with. If it was Australia, with an ASIC airfield and there was a security protocol being followed by everyone on the field, those terrorists would not have passed the ASIC screening so not allowed to be trained, so the attacks wouldn't have occurred.
Yes, it might not tickle your fancy, but Australia is a commonwealth of six sovereign states and two territories, so there are issues to be discussed and arrangements to be made when joint action is needed.
I've just answered your series of scenarios, but in reality the threats and reactions might be quite different, but the ASIC card cost is less than an hour's flying for most people.