What are you talking about? The US navy protects the commercial shipment routes around the world.
Likely soon corporate owned drones will protect commercial shipping routes I would think. Not sure if bad actors (pirates?!) will have their own drones.
I’m sure that China would be happy to take over.
The gratuitous hostility undermines your point.
Before the US Navy did that, the Royal Navy did. The work needs to be done, but it doesn't have to be the US doing it.