Fallout - Fallout: Raider Road

This makes me think though, just how is Australia like in the Fallout universe? Come to think of it, how is most of the world in general? The games only ever take place in the US since the game is going for a "what if the Cold War lasted more than 100 years and ended in nuclear disaster?" kind of feel, but I admit I can't recall much lore discussing what happened to places like Australia, Europe, or heck even Canada and Mexico since they border the US.