From the outside looking in...it appears Canberra is the main threat to Australia.
Like Washington DC and in fact it is a copy. Australian Capital Territory and Canberra is the main place in the ACT. The Australian Federation is a copy of the American Federation and in particular the Senate. State Premiers are the counterpart of your state Governors.
I would say most issues in Australia are as a result of almost the whole population living in one of five big cities and also up and down the east coast.
You nailed it. In the US when you come to the nub, it's rural vs urban, in politics, tradition, basic human values, even dare I say it...race. Anybody that speaks of these bitter divides ever coming together...doesn't even recognize the problem. The urban and coastal ruling class has brought us to this unbridgeable split. Time will tell, but I see Balkanization as the only peaceful answer.
