Dunno where you get your 2/3rds from,
Aus and NZ are islands in the pacific with no bordering countries, the strict immigration is on those that come by boat, and that's not so much about the ones that arrive but those that don't, for every 1000 that make it ashore.. 5,000 drown, and that 1000 that do make it, find they are in crocodile country with 4000 miles of desert in front of them. So its more about curbing the Indonesian people smugglers that sell the dream.
What they do here that seems to be lacking in the USA is really clamping down and fining companies that employ non citizens, if you caught here employing them... say bye bye company basically.
60% of Australians have at least one parent that wasn't born in Australia
https://www.sbs.com.au/yourlanguage/...intake-2018-19
180k immigrants a year, 24 million population, so to be the same, USA would need closer to 2.5 million immigrants a year. And if your not bringing in at least that many.. your fucked due to the aging population base... and of course.. CHina
I think the current American immigration laws are nuts, same with voting laws. What the solution is I have no idea, certainly need to start clamping down on companies employing them and making the path to citizenship more easy/ avaliable.