Last time an international power tried to heavy Australia to remove the PBS Australia lost in court. So we needed the whole country to vote to change the Australian Constitution. Which we did.
These US firms are dreaming. Their actions will simply stoke anti-US sentiment and lead to the sort of buyer's strike currently being conducted by the people of Canada.
"Australia defends Pharmaceutical Benefits Scheme as US companies urge Trump to impose reciprocal tariffs"
https://www.abc.net.au/news/2025-03-19/australia-defends-pbs-us-pharma-urges-reciprocal-tariffs/105072750