Let's pretend that the US created the internet as a whole and that it wasn't created by a joint effort from different actors around the world. That still doesn't mean they own the internet today like you continue to imply. And consequently means that any group, organization, or country which chooses to deploy alternate DNS Root servers (forked or fully custom) on their own DNS providers is well within the right to do that without needing to build their own internet, and simply use all the non air-gapped infrastructure they have already.