im australian, and im actually learning about this in school atm.
well in the beginning good ole Aus was connected with the home land alot.
in WWI britain declared war with germany, it was seen as Australia's responsibility to help out britain by sending troops.
during wwi a famous battle was fought in turkey.
the Australian troops and New Zealand troops, showed great mateship and a sense of nationhood between each other. many australians died during this time.
in WWII britain again called on Australia to help them again. this time Asutralia had grown up from the experiances from world war one and had lost some of the mother love with britain. Australia sent their troops to help the british in the middle east.
during the time they were in the middle east the japanese had started their invasion of the pacific region, the dutch east indies (indonesia) was finally overcome by the japanese and the Australian defense group wanted to call the Aus middle east troops back home, to help defend from the Japanese in indonesia(indonesia is the closest neigbour to australia).
Britain refused so Australia sent them home anyway. this was one key element that helped lose the connection with the British commonwealth.
Australia called for the US to help and they did. Aus had better ties with the US at this time until, the american troops stole all our troops wives. then we got pissed off, So we hated them.
So this Australia became more independent to the commonwealth.
We didnt become republic due to the fact that Australia has a very Large coastline and quite a small population. this makes it hard to defend.
we had a good relationship with the commonwealth during world war one because australia in those times had a very very small population.