Our armed forces deploy overseas on a variety of missions that include NATO support as well as peacekeeping. More generally, a standing army helps counterbalance the threat of land invasions in a way that a navy on its own could not. Thirdly, our armed forces are often used for humanitarian purposes such as supporting the country during our (not infrequent) natural disasters, e.g. flooding or bushfires.

Have you not heard about the wildlife in Australia? From what I've read, every step you take outdoors, something is trying to kill you. I'm surprised every Australian school child isn't packing a rocket launcher.

Crocodile Dundee didn't need no rocket launchers man. An Akubra hat was enough.

...and that knife. That was a knife!

The ADF are key to the Coalitions mission: when America wants something dirty done, that will not have the complication of civilian oversight should an investigation be necessary, they come to the Australian Defence Forces...