There's a huge difference between the US having an international network of law enforcement co-operation (even if we do have boots on the ground doing investigative work) and the Chinese Police Stations going out and strongarming people individually.

Countries are supposed to have a monopoly on the use of force within their borders. Lending it out is good international relations. Not that it's never acceptable to violate that - The Takedown of Bin Laden was a law enforcement action taken overseas by the US military in a country that was not informed until after it was on it's way out.