Misstranslation.
Should be "Central Kingdom."
Not “rule” in the sense of physically occupy. They would define “rule” as having “hegemony” over the barbarian nations. (Barbarian is defined to be all nations\people not China.) Some nations are less “barbarian” then others. Traditionally that was defined as physical distance from China - the further away the more “barbarian “. To the true Han foreigners are dirty smelly & unclean.
“Hegemony” means indirect control through native rulers, it also means a form of economic control, a sort of colonialism. They view that as payback for the “400 Years of Shame - meaning Western domination\control” - title of a party congress speech (Given some 20 years ago!) Achieving “Hegemony” over the US is basically what they are doing through Biden and any other US politician who snuggles up to them.