Fris B.
I don't wish to labour the point, but Sweden, with a population of less than 10 million supports its own defense industry and has an indigenous strike aircraft.
Taiwan at 23 million population also has its own aircraft and associated industry (and technological spin-offs)
Meanwhile, Australia had access to 40-odd "prototypes" for 40 years and could only sit passively and wait for some US defense giant to sell it some outrageously priced, new-fangled aircraft that may or may not be better.
So, the nation "couldn't afford to maintain the existing fleet", but it could apparently afford to spunk gazillions (insert blank cheque here) on an unknown quantity.
Meanwhile, our trade balance is a disaster (despite a "mining boom" - check out how little impact this boom has had on our trade and current account!) and the nation is in terminal decline in terms of education standards, employment and industrialization.
A complete failure of government of all stripes.
PS: buying expensive future landfill on the credit card isn't just a defense problem - it's a national disease!