Australian contribution: helped British surrender at Singapore, ran around in the jungles of New Guinea, provided coast watchers to the US Navy.
US contribution: everything else, from Guadalcanal to Okinawa to Tokyo Bay.
If it wasn't for the bloody Yanks, your mother would have been a "comfort lady" for the Japanese Imperial Army, and you would be a "half caste" bowing low while serving Saki in a Japanese Imperial Army brothel in Melbourne.
You're very welcome for your freedom, now go ahead and slime the nation that saved your freedom. We can take it, we are well used to being slobbered on and nipped by the American protected puppies in Europe.
Trav?
Take the chip off your shoulder and stick it where the sun don't shine, bud.