The whole premise of the AUKUS deal is that Australia would act as a proxy for the US and UK, should China ever invade Taiwan.
To fill that role, Australia needed long-range submarines. Which would be purchased at Australia's expense.
But the Trump Administration has so far shown it will side with authoritarian regimes and parties over liberal democratic governments.
Most notably, in Ukraine and in tariff policy.
It raises the fundamental question: Would the US come to the aid of Taiwan if it were invaded by an authoritarian state (like China)?
If the answer is no, then fundamentally AUKUS is dead in the water.