Just the thing against small boat swarming. It would take the USN a decade to adopt such an obvious weapon.
That said, reading the blurb, sounds like at leat one class of Aussie navy ship has only .50 caliber machine guns for self defense? Good luck shooting down an ASM with that............
No - although I can see how this part of the article could give you that impression: 12.7mm machineguns on the LHDs, Anzac class frigates and Armidales
Fortunately that 12.7mm is only describing those vessels secondary armaments. The LHDs have four 25mm cannon as their main defensive armament (although they will primarily rely on their aircraft and escorts for defence - they are also currently looking at getting the Phalanx system in a few years), and each of the Armidale-class patrol boats (which are basically similar to USCG cutters - we don't have a separate Coast Guard, that role being part of our Navy) have one as well. The ANZAC class frigates each have a five inch main gun, Sea Sparrow missiles, and Mark 46 torpedoes.
Good luck shooting down an ASM with that............
We've also got the Nulka system to help with that type of protection - an Australian created system that the US and Canada are now adopting as well (I believe the USN has actually had to use it a couple of times recently - I don't think any RAN ships have been attacked in a way that required its deployment). Nulka doesn't shoot the ASMs down - but it can make them miss.