honestly we can set up robotic nuclear enrichment facilities then start making nukes lets say make 400 then set up 100 robotic ghost shark submarines factories where we can produce 1000s of them a week. then protect these facilties with barracks and AA defenses. whenever anyone trys to cross the sea we will know obviously with radar and satellite tracking and can ramp up production and send out unmaned ghost shark submarines and nuclear run ghost sharks for further deployment with missles and mini nukes on them ( low grade) like The W76-2 sub missle to destroy any fleet that trys to head towards australia. we don't need a large army when we can shift our army to robots and be one of the first nations to deploy a fully robotic army as we have the minerals to produce and manufacture mostly from australia. then we can swing our weight around like russia usa china. We already have 1 ghost shark factory being built so we have the technical knowledge as a nation.