It is because of our early history - heavy with hubris - with introduction and escape/release of cane toads, prickly pair, tiger pear, rabbits, foxes, camels, fruit fly, etc ... that Australia is now extremely cautious.
The cane toad was introduced intentionally (it just turned out to be a bad idea). It was also the 1930s.
That was in the 1930s.. quite a stretch to project that failure to modern times.