Unfortunately our Government holds the view that we're so remote from everyone, no-one's going to bother attacking us. (We're not scared of you Aussie yobbos!
)
Seriously though, we've had running defence cuts since the early '90s (I was one of 1100 Defence personnel who lost their jobs in the '92 defence cuts).
The Skyhawks were deemed too old to keep upgrading, and negotiations were made in 2001 to rent F-16s, before the Government decided it was all too expensive and pulled the plug on the entire Strike Wing.
Our 10 year old Aermaachi MB 339CBs were sold off pretty quickly (to Indonesia), but the Skyhawks have been a point of controversy among various parties (predominantly the US military), with the result that they are still sitting on the spot 10 years later rusting away...