…the Allies vowed to never again allow regional hegemons

IMO this was primarily the US under FDR (Bretton Woods Accords) offering access to the US consumer market and blue water transport overwatch on its own dime, which las lead to both the post 45 ‘long boom’ and what we now call the ‘global order’.

That said, when you compare navies, look at the 'legs' of each (as a side note, 'legs' was why it was primarily the US fighting Japan in the Pacific, not the US plus UK). We took the longer-legs-better lesson to heart, and thanks to Admiral Rickover's vision our navy is now primarily nuclear powered giving the US navy global reach.

As best as I can tell, China's new 'Fujian' carrier is diesel or gas turbine (someone please correct me if I'm wrong), so there's a need to refuel at least once a week.

Consider what happens if the US starts interrupting the flow of oil from the Persian Gulf to China, far outside the effective range of the Chinese navy. Yes, the Chinese can travel further than a couple of days from where they have refuel bases, but the fuel has to be available (oilers). Unless I'm wrong on the propulsion plant, of course.