I live in the USA. Do the Victoria police have any sort of interpol/international agreement that may impact my passport status or drivers licence in the USA?
Well then pay the fine and move on with your life.
If you do that, it will have no effect on anything in the US.
If you ignore it, then it will meet you at the airport the next time you come home.
No, they won't chase you.
The unpaid fine will sit on a database until you return.... and as I said above, will (metaphorically) meet you at the airport.
No lawyer acting ethically would advise you to leave the fine unpaid.
To do so is to treat the infringement, and the system of law that produced it, with contempt.