In the late 1800's we were worried about Russia Japan and Germany. We looked to the Motherland to protect us. Queensland invaded New Guinea in 1883 and Britain to it to f%$# off back to the banana fields. This allowed Germany to annex NG in 1884. Along came Federation coz we worked out the British were aholes and weren't going to protect us. The sandgropers were the only smart ones as they got a railway out of it for nothing.
Next came Japan in WW2 as possible invaders. Instead we got 100's of thousands of yanks here. Like sending in the cane toad after the cane beetle!
Now.......let's look at our offence;
Sudan 1885 New Zealand 1840s + 1860s South Africa 1899 - 1902 China 1900 - 1901 New Guinea 1914 (albeit to kick the squareheads out) Turkey 1915 Middle East 1915 (Ottomans owned it then) Viet Nam Afghanistan Iraq
I think the rest of the World needs a defensive line against us not the other way round - we are very nasty!!