You see, Australia has a 40,000 plus year predicament.
too big a landmass; for too small a population; with too many resources.
During the last big invasion - by the English - the people of the land mass back then were lucky that the invaders were a civil lot.
Can we be so sure that the next time this landmass is invaded that the invaders will be so civil?
Perhaps we are better to let in immigrants bit-by-bit and build up our numbers so that when the next invasion arrives we can fend them off (just in case they are civil).
Or else we could just float along with 20 or so million and hope against hope.
but that ain't possible. In a world of resource-hungry people; Australia's population WILL increase one way or the other.
