For approximately 100 years (c.1850-c.1950) Australia had a policy of preferring immigrants from Britain and European countries. The origins of the policy are rooted in the gold-rushes of the 19th century, and tensions between the majority white miners (both local and immigrant) and Chinese immigrant miners. In many cases the Chinese miners were more successful than their white counterparts due to their hard work ethic and ability to work cooperatively amongst themselves - traits that hold true today. This success, combined with the social barrier that different culture and language present, caused much resentment from whites leading to protests and riots.
The subsequent restrictions on non-white immigration were later referred to collectively as the ‘White Australia Policy’ (WAP), although this was never the official name. It should also be noted that immigrants of non-white ethnicities were never expelled from the country on the basis of their ethnicity during this period. Many Chinese Australians can trace their ancestry back to the miners of the 19th century.
Today the common narrative in academia and the media is that this policy was a bad thing, a stain on Australia’s history, and that we’ve progressed beyond such primitive and parochial ideas. To the contrary, I think the WAP has been a net positive, and modern Australians owe a debt of gratitude to the political leaders of that era for their foresight and resolve. The WAP allowed Australia to pass through its crucial adolescence years as a nation with one overarching culture - British - with other highly compatible Western European cultures being mixed in. This provided a solid foundation on which to build a national identity - something that modern Australians (of all ethnic backgrounds) can all unite around.
This is not to say that people with white skin or with european ancestry should get any preferential treatment or privileges - not at all!! It is to say however that someone from another cultural background living in Australia should be expected to learn to speak English & adopt the values of western civilisation: respect for individual rights, respect for the sanctity of life, rule of law, treating people fairly irrespective of gender, age, sexuality.
If Australia had not implemented the WAP then it is unlikely Australia would have a national identity that spans the entire continent. As such, it’s unlikely that we could have formed the commonwealth of Australia, and instead may have ended up with smaller nation states, divided by culture and language. In such a scenario, it’s hard to see how we would have withstood military interference from the likes of China or Indonesia, as it’s unlikely we would have the strong military and economic ties we currently enjoy with America.