PLovett;
Invading Australia by force is not an acheivable option. You would require at least one Armoured Division and there is nowhere to land them plus maintain their logistical support. (I can debate this by PM if you like. I am a retired Army Officer).
I mentioned the matter to concentrate the mind on how serious our invasion by stealth is. And that is happening now.
control the trade routes, i.e. S. E. Asia.
You mean like the people smugglers routes?
BTW, I didn't think the Channel was 125 miles wide, but you do illustrate the point I made in para 1. It's not just the landing, but maintaining the physical lines of communication. Oh, and the last free sea lane left in the World is The Southern Ocean.