A truism is that International Law constitutes codified politics bestowed by Great Powers.
More specifically if breaking non-proliferation conventions strengthens the Western Alliance then the NPT can be ignored. The NPT is "Treaty on the Non-Proliferation of Nuclear Weapons" commonly known as the Non-Proliferation Treaty hence NPT.
The NPT is not only about nuclear weapons. Its "Third Pillar" is about the peaceful use of nuclear energy.
It appears that if acts promoting nuclear proliferation, on balance, favour the US/Western Alliance, then key parts of the NPT, and its spirit, can be ignored.
So running counter to the NPT's Peaceful Use of Nuclear Energy is the US and UK, under AUKUS, assisting Australia to build warlike nuclear propelled submarines.
The prospect of the US and UK exporting 93+% weapons grade HEU to be used in the reactors of Australian nuclear submarines runs even further from "peaceful use". Also see Wiki's reference and linked explanations to 93% HEU.