Our foreign debt, while not insignificant, pales in comparison to the total amount of debt held by US banks. US banks which are publicly traded and owned by a variety of stock holders, hedge funds and holding companies. And who have been granted authority by the US Congress to create US currency by loaning it into existence.
China on the other hand owns all of it's banks, and therefore owns the trillions of dollars of assets and hundreds of billions of annual revenue.
While we are approaching 60 Trillion total owed to US banks ( Federal, state and local governments, + private and corporate debt) all of China's domestic debt owed to Chinese banks becomes revenue of the nation.