As a proud Chinese American I am here to say this: This so called "aggressive imbecile" was never elected by a majority of the people. He never got the most votes. He never got a majority approval. He was impeached by Congress. His entire election was just a mistake. And now he has been defeated for re-election the first president to do so since 1992. Please do not take him as an indicator of American intention. Quite the opposite.
Trump only lost re-election by <50k votes in 2-3 swing states. The Democrats also got savaged in the House and state elections. The GOP and Trump made massive inroads among Latinos, the demographic future of the United States' swing states. You're either lying or completely uninformed about American electoral politics if you think Trump was a one off aberration.
What the 2020 election showed us is that the PRC should prepare for a base case of GOP annihilation of the Democrats in the 2022 midterms followed by some "America First" Republican without Trump's baggage winning spectacularly in 2024.
Even then, it's worth noting that military/national security planners' job is to plan for the bad end of the baseline scenario. The baseline is economic cold war. The bad end of the base case is open warfare with the US. It's best to pre-emptively prepare for near assured American hostility by smashing its client states while they are in a state of internal disarray.
In other words, there is pretty much no downside to breaking Australia and no upside in refraining from doing so.